JPS6022765B2 - Industrial robot posture comparison display device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention particularly relates to a posture comparison display device that is most suitable for a partial motion correction method for a CP-controlled industrial robot.

Conventionally, for example, painting with a spray gun on a painting line for automobiles, etc. requires relatively skill because it tends to cause uneven coating, and for this reason, it is possible to repeat the painting work accurately. Industrial robots are being adopted.

By the way, memory regeneration type industrial robots are equipped with PTP (
POINT TO POINT) method and CP (CON
TINUOUSPATH) method, the PTP method, when teaching a series of work movements, gives the coordinates of some points in the middle, and performs auxiliary calculations between the points to drive the regeneration, and the CP method , a series of work operations in succession (
Recording is performed at a sampling period of approximately 10 hs, and playback is driven. For teaching using the PTP method, a control box or the like is generally used to remotely control the desired position and position.
The method used is to press the record button when you are in the correct position. This method saves memory because the amount of data to be recorded is small, and it is inherently easy to modify the data, but because calculations are performed by interpolating between points in the middle of the work operation, , it is difficult to obtain smooth movements, and it is particularly unsuitable for use as a painting robot for overcoating work. On the other hand, the CP method reproduces the work motion as taught, resulting in smooth movements, and allows an expert to repeat the motion as taught. If there is a work area, there is the inconvenience of having to start teaching all over again from the beginning.

When a partial motion correction is performed on the above-mentioned CP-controlled industrial robot, the present invention aims to change the posture of the robot to the same original force at the start of the correction so that the original position data and the corrected position data are smoothly connected. It was made so that it can be reproduced.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings, which are adapted to a partial motion correction device for a CP-controlled industrial robot.

As shown in FIGS. 1 and 2, a CP-controlled industrial robot 1 adopted in an automobile painting line is mounted on a turntable 3 on a base 2. A vertical arm 4 and a horizontal arm 5 are provided, a spray gun 6 and a manual grip 7 are attached to the tip of the horizontal arm 5, and each hydraulic cylinder 8, 9, 1 is connected to each arm. 4 and 5 are rotated and swung, the spray gun 6 is moved along a predetermined coating trajectory, and paint is sprayed onto the automobile body 12 conveyed by the conveyor 11.

Basically, in this robot, an expert in painting work manually moves the spray gun 6 to teach the work operation, and the position of the spray gun 6 is detected by a position detector 13. After the data is sequentially stored in the storage device 14 as a work program, the robot drive device (hydraulic circuit, etc.) 15 is controlled according to the stored work program, and the spray gun 6 is regenerated.

Next, the CP control device of the robot 1 will be explained.

As shown in Figure 4, the mode is set to [Normal] on the operation panel 16.
A mode changeover switch 17 for switching between and [partial correction], [playback] and [memory], a start button 18 and a stop button 19, and a section instruction switch 20 are arranged, while a control circuit 21 and a control circuit 21 for recording and playback are arranged. storage device 22;
A shift register 23, a position detector 13 and a robot drive device 15 are provided for the robot.

The mode selector switch 17 is set to [Normal] and [Memory] for normal teaching, [Normal] and [Reproduction] for normal reproduction driving, and
[Partial correction] [Reproduction] switches to a mode in which playback is performed during partial correction, and [Partial correction] [Memory] switches to a mode in which teaching is performed during partial correction. When teaching in normal times, turn the mode changeover switch to [Normal] memory], press the start button 18, and turn the spray gun 6 of the robot 1 into the spray gun 6.
For example, as shown in the upper part of FIG. 3, the car pod 12 is moved from the starting position A to the position B, for example, as shown in the upper part of FIG.
When the spray gun 6 is moved in a rectangular frame shape through C and D to the end position E (start position A), the position of the spray gun 6 is detected by the position detection device 13, and this position data and the on/off data of the function switch 24 are detected. is stored in the shift register 23 at a sampling period t of 10 hs, and furthermore, this data is combined with data such as fluctuations in the conveyance speed of the conveyor 11 by the control cycle control circuit 25 in the control circuit 21. Then, they are sequentially stored in the storage device 22 as a work program.

During normal playback, when the mode changeover switch 17 is set to [Normal] and [Playback] and the start button 18 is pressed, the robot driving device is 15, the spray gun 6 of the robot is regenerated and driven from position A through B, C and D to position E in synchronization with the transport speed of conveyor 11 as taught.

In addition, each time the normal teaching or playback described above is completed, the stop button 19 is pressed and the shift register 23 is
and the hydraulic pressure of the robot drive device 15 is turned off.

On the other hand, the partial motion correction device attached to the CP control device is composed of a block for instructing a correction section and a block for correcting the distance between the connection portion between the corrected position data and the original position data. The block for instructing the correction section includes the section instructing switch 20, the selection circuit 31, and the data number counter 3 for the correction recording storage device 30.
2, a start point register 33, and an end point register 34.
, a comparison calculation circuit 35, a display circuit 36 for displaying remaining time and indicating a section, a register 37 for storing posture, a comparison circuit 38, and a display circuit 39 for displaying posture.

For example, for the position data of the spray gun 6 shown in the upper part of FIG. 3, as shown in the lower part of FIG.
If you want to partially correct the gap into a wave shape, set the mode selector switch 17 to [Normal] or [Playback] during playback during partial correction.
When the user presses the start button 18, the spray gun 6 of the robot 1 will be regenerated as instructed in the same manner as in the above-mentioned "normal regeneration."

In the process of regenerating the spray gun 6, the operator watches the movement of the spray gun 6 and adjusts the work operation during the correction period D-
The starting point D and ending point E of E are indicated by manually pressing the section indicating switch 20.

First press of section indication switch 20 (instruction of starting point ○)
When selected by the selection circuit 31, the data number counter 3
The starting point data number according to the sampling period t of the position data of the spray gun 6 counted by 2 is stored in the starting point register 33 via the AND circuit 40, and at the same time, the attitude data of the spray gun 6 at that time is stored in the attitude memory register 37. Then, when the selection circuit 31 selects the second press of the section designating switch 20 (designating the end point E), the end point data number is stored in the end point register 34 via the AND circuit 41.

In this case as well, when the playback ends, the stop button 19 is pressed. When teaching partial correction, when the mode changeover switch 17 is set to [partial correction] and [playback] and the start button 18 is pressed, the robot's spray gun 6 operates as taught in the same way as in the above-mentioned "normal playback". will be driven by playback.

In the process of regenerating the spray gun 6, when the spray gun 6 reaches the starting point D of the correction section D-E, if the comparison calculation circuit 35 determines that the data number of the starting point D matches the original position data number, the spray gun 6 is input to the control circuit 21, the recording/reproducing storage device 22 is stopped,
The spray gun 6 stops at the starting point D.

Next, set the mode changeover switch 17 to [partial modification] [memory]
When the start switch 18 is pressed, the comparison circuit compares the attitude position data of the spray gun 6 at the starting point D stored in the attitude storage register 37 with the current attitude position data of the spray gun 6 operated by the operator. 38, the position comparison display circuit 39 displays the deviation digitally, for example, and the operator operates the spray gun 6 to keep the deviation within an allowable range.

When the conveyor 11 is started in this state, {the conveyor 11
The control period control circuit 25 adjusts the control period (corresponding to the sampling period t during storage) so as to synchronize with the movement of the data number counter 32 in accordance with the control period. In the process of advancing the data number, when the data number of the data number counter 32 matches the data number stored in the starting point register 33, a signal is sent from the comparison calculation circuit 35 to the control circuit 21 to determine the position of the spray gun 6. Start storing data. That is, in this state, when the operator teaches a correction operation by moving the spray gun 6 of the robot 1 in the correction section D-E from the start point D to the end point E in a waveform, the position detector 13 detects that the spray gun 6 The position of the conveyor 11 is detected, and this position data is stored in the shift register 23. Furthermore, the control circuit 21 combines it with data such as fluctuations in the conveyance speed of the conveyor 11 by the control period control circuit 25, and corrects it as corrected position data. It comes to be stored in the storage device 30 for recording. In the above correction work, the time t of the correction section D-E is calculated by the comparison calculation circuit 35, and the display circuit 36
may be displayed digitally, for example, and the operator is instructed on corrective work actions to be completed within a predetermined tolerance of the time.

If the teaching is not completed within this allowable range, the correction position data stored in the storage device 3 is erased.
The correction work operation is taught again regarding the correction section DE. To further describe the robot posture comparison display device, if the operator wants to start teaching the robot from a previously specified posture, it is easy for the operator to do so without having to memorize the specified posture. In particular, when correcting a partial motion, the corrected position data and the original position data need to be connected smoothly, so it is desirable that the position be the same as the original when starting the correction. It was established for this purpose.

In principle, this robot posture comparison display device, as shown in FIG. an instruction and storage device 52 to store the posture, a tolerance setting device 53 to set the tolerance range of deviation from the specified posture for each degree of freedom of the robot 1, and a storage device 52 to store the stored posture and the posture currently taken. A display device 5 that compares each degree of freedom with a comparison device 54 and displays whether or not each degree of freedom falls within an allowable range, and if it is out of range, to which side and by how much.
It consists of 5.

The operation will be explained using the flowchart shown in FIG.

'1' Teach robot 1.

■ Regenerate the robot 1, and press the switch 50 at the point when it is deemed necessary to start partial correction.

At this time, data regarding the posture of the robot 1 is stored in the storage device 5.
It is written in 2. {3' Next, the operator moves the robot 1 so that it assumes the posture memorized in '21.

At this time, the display device 55 (see FIGS. 6a and 6b) shows whether the posture has deviated or not for each degree of freedom, and if so, to which side and by how much. By moving each degree of freedom in the direction that eliminates the deviation, a predetermined posture can be achieved. '4) Allowable ranges can be set in advance for each degree of freedom regarding the amount of positional deviation, allowing slight deviations to be ignored, reducing the burden on the operator.

The display device 55 includes a display section 56 that digitally displays the amount of deviation and its direction (eleven) for each degree of freedom, as shown in FIG. On both sides of the round LED 57 that lights up when the tolerance is within the tolerance range, there is a triangular L that displays the amount of deviation and its direction (11).
It would be convenient to adopt a display section 59 provided with EDs 58, . . . , 58.

Note that it is also possible to employ a display section that changes the tone color for each degree of freedom and changes the intensity of the sound depending on the amount of deviation. On the other hand, when teaching the above-mentioned partial correction, the correction position data stored in the storage device 301 for correction recording has an error within the allowable range at the connection part with the original position data at the above-mentioned Onadai point D and the end point E. There is a step (step), and it is necessary to make this step continue smoothly and then replace it with the corrected section of the original position data stored in the storage device 22 for recording and reproduction.

Therefore, in order to make the corrected position data continue smoothly with the original position data, an arithmetic unit 42 for interpolation calculation is provided between the storage device 30 for correction recording and the storage device 22 for recording and reproduction.

The interpolation calculation by the calculation unit 42 employs a linkage algorithm.

In principle, in the case of interpolation calculation of the starting point D shown in Fig. 8,
Data for four sampling periods t before and after the boundary point ○ between the original position data × and the corrected position data Y are subject to linkage.

In other words, the total period is 80 dishes (10 dishes x 8). First, each point of the original position data X is represented as oi, and each point of the correct position data is represented as ni.
Assign a number such that i=0 to 8).

In addition, the points calculated by linkage calculation are as follows. 〜Part 8. Divide the data of oo and the data of the mountain into four equal parts, respectively oo,
SI'S2'S3, ~.

〆o=〇.

So, = (o, ×70s, ×1)/8 〆2 = (〇2X60S2×2)/8 So3 = Chestnut X50S3×3)/8 So4 = (〇4X40n4×4)/8 Evening 5 = (Takumi x 30n5 x 5)/8 So6 = (〇6X20n6×6)/8 Evening 7 = (〇7×10n7×7)/8 Part 8 = and The linkage data Z is calculated as follows.

Similarly, the end point E is also subjected to interpolation calculations, and the smoothly corrected corrected position data is replaced with the corrected section of the original position data.

FIG. 9a shows an example in which the connecting portion of the starting point D is smoothly corrected using the linkage algorithm described above, and FIG. 9b shows an example in which the connecting portion of the ending point E is similarly corrected smoothly.

Figure 9c shows the connection between the end point E and the corrected position data Y.
This is an example in which when there is time remaining, that is, when the partial motion correction is completed early, the joint portion is smoothly corrected while waiting. The operation of the partial motion correction device configured as described above will now be described.

In actual painting work, the entire painting trajectory for the automatic body 12 is divided into several plots, and corrections are made in units of blocks.

As shown in Figure 10a, these blocks are determined prior to teaching, and the area from the start position A to the end position E is divided into blocks ■ to ■. or the first method
As shown in Figure 0 b, the part that seems to need correction based on the playback operation is regarded as one block, and the connecting part of the block (the part that is not painted) is the starting point ○ and the ending point E in the above figure. There is. Instructing/memorizing the correction section using the former method (2) Set the mode selector switch 17 to [Normal] and [Memorize] to teach the normal work operation as described above.

■ Set the mode selector switch 17 to [Normal] or [Playback],
The robot 1 is regenerated, the paint condition is checked, the block to be repaired is determined, and the position data numbers corresponding to the start point D and end point E of the correction section are stored in the start point and end point registers 33 and 34.
to be memorized.

Instructing and memorizing the correction section using the latter method■ After setting the mode changeover switch 17 to [Normal] and [Memorization] and teaching the normal work operation as described above, turn the mode changeover switch 17 to [Normal] and [Reproduction]. Then, drive the robot 1 to check the paint condition and memorize the approximate position of the block to be corrected.

■ Keep the mode changeover switch 17 set to [Normal] or [Reproduction], drive the robot 1 for regeneration, press the section instruction switch 20 at the female joining point D and the end point E of the correction section, and follow the starting point D and end point rule of the correction section. The corresponding position data numbers are stored in the start point and end point registers 33 and 34.

Correction work procedure using the former and latter methods■ When the mode selector switch 17 is set to [Partial correction] or [Regeneration] and the robot 1 is driven for regeneration, when the spray gun 6 reaches the starting point D, the comparison calculation circuit 35 sends the spray gun 6
A signal for stopping is inputted to the control circuit 21, the recording/reproducing storage device 22 is stopped, and the spray gun 6 is stopped at the starting point ○.

Next, when the mode selector switch 17 is set to [partial correction] or [memory], the operator moves the spray gun 6 of the robot 1 from the starting point D to the ending point E and teaches a correction operation, and this position data is used as the correction position data. It is stored in the storage device 30 for correction recording.

In the above correction work, the display circuit 36 shows the correct section D-.
The time E is digitally displayed, and the corrective action is taught to be completed within the allowable time limit, while the posture comparison display circuit displays the posture of the original position data and the operator's corrective action. The display unit 56, as shown in FIGS. 6a and 6b, shows the deviation from the posture of the corrected position data that teaches
59, and the operator instructs the operator on correction operations to keep the amount of deviation within an allowable range.

■ The corrected position data stored in the correction recording storage device 30 is configured so that the connecting portions with the original position data at the start point D and the end point E are smoothly continuous by the calculation unit 42 through interpolation calculation using the linkage algorithm. After that, the position data is replaced with the corrected section DE of the original position data stored in the storage device 22 for recording and reproduction. (2) Then, the reproduction drive of (2) is performed again to check whether the partial motion correction has been performed accurately.If it is inaccurate, the partial motion correction work of (1) to (4) is repeated again.

As is clear from the above description, the present invention compares the posture stored in the storage device with the current posture, and determines the presence or absence of deviation, the direction of deviation, and the amount of deviation for each degree of freedom. By displaying the robot externally, it becomes extremely easy for the operator to recreate the robot's original posture.
Particularly when performing partial motion correction in a CP-controlled industrial robot, the original position data and the corrected position data can be smoothly connected.

[Brief explanation of the drawing]

Figure 1 is a basic configuration diagram of a CP-controlled industrial robot, Figure 2
The figure is a perspective view of an automobile body being conveyed by a conveyor.
The figure shows the relationship between the work movement pattern and the sampling period, Figure 4 is a circuit diagram of a CP control machine incorporating a partial movement correction device, Figure 5 is a circuit diagram of the principle of the display device, Figure 6 a and FIG. 6b is a front view showing an example of the display unit, FIG. 7 is a flowchart regarding the display device, FIG. 8 is a diagram explaining the principle of interpolation calculation using the linkage algorithm, and FIG. 9a,
FIGS. 9b and 9c are explanatory diagrams of specific examples of interpolation calculation by the linkage algorithm, and FIGS. 10a and 10b are perspective views showing divided blocks of the coating trajectory. DESCRIPTION OF SYMBOLS 1...Robot, 6...Spray gun, 12...Automatic body, 13 Position detector, 14...Storage device, 15...Robot drive device, 16...Operation panel, 17...Mode switching Switch, 20... Section indication switch, 21...
- Control circuit, 22... Storage device for recording and reproduction, 23...
・Shift register, 25... Control cycle control circuit, 30...
Correction record storage device, 32...data number counter,
33... Register for starting point, 34... Register for ending point, 35... Comparison calculation circuit, 36... Display circuit,
39... Display circuit, 55... Display circuit, 56, 59
...Display section. Figure 1 Figure 2 Figure 5 Figure 6 Boat dimensions Figure 7 Figure 8 Figure 9 Figure 10

Claims (1)

[Claims] 1. Detect the position of the controlled object that is linked to the operation of the robot whose work operation is to be taught manually using a position detector,
In an industrial robot that sequentially stores this position data as a work program in a storage device and then regenerates and drives a controlled object according to the stored work program, a process of regenerating and driving the controlled object. In response to a manual operation such as a switch, a memory device that stores the robot's posture for each degree of freedom, and a tolerance for the amount of deviation from the specified posture for each degree of freedom of the robot are set. A comparison circuit compares the orientation stored in the tolerance setting device and the storage device above with the current orientation, and externally displays the presence or absence of deviation, direction of deviation, and amount of deviation for each degree of freedom. 1. A posture comparison display device for an industrial robot, characterized in that it is equipped with a display circuit.