JPS5856783A - Industrial robot - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] This invention relates to an improvement of an industrial playback robot,
Particularly regarding things that make teaching easier when repeating the same pattern on a straight line 0 For example, welding while repeating the same pattern on a straight line is widely performed as weaving welding or tack welding, and For back robots, it is usually necessary to teach all information about each point of the process. In order to eliminate this complication, prior art applications were filed by the same applicant as the applicant of this invention, and Japanese Patent Publication No. 52-18782 and Japanese Patent Publication No. 58-4, respectively.
It is disclosed in Japanese Patent Application Laid-open No. 828 and Japanese Patent Application Laid-open No. 14189/1989 A8. However, in these conventional techniques, it is only necessary to teach the position information of each point in one cycle between the start and end points of a certain machining line.

This can only be carried out automatically up to the end point, and if you want to repeat the same butter on another processing line, it is necessary to carry out similar teaching again at that point.

Therefore, the inventor of this invention came up with the idea that the above-mentioned complications could be further resolved by teaching a repetitive pattern once and making it possible to repeatedly execute this on other machining lines. This is what we have come to complete.

Embodiments of the present invention will be described in detail below with reference to the drawings.

FIG. 1 is an overall view including a rectangular coordinate welding robot (RO) that forms the background of this invention and is effective in carrying out this invention, but this invention is not limited to this embodiment.

l is a well-known rectangular coordinate (Xs3't2
) 4 in the vertical axis, configured at the terminal of the robot RO.

2 is one arm which is supported at the lower end of the vertical axis l so as to be pivotable about the axis l.

A second arm 8 is supported at the tip of the arm 2 by an oblique shaft 8a so as to be able to rotate β. At the tip of the second arm 3 is a processing tool (MIG welding torch T in this example) as an end effector.
A gripping tool 8btl for gripping is provided.

The shaft 1, the shaft 8a, and the central axis TC of the torch T are constructed so that they can intersect at one point P; furthermore, the torch T
is arranged so that its welding operating point can coincide with point P. Thus, by controlling the angles α and β, the attitude angle θ and the turning angle ψ of the torch T with respect to the vertical axis 1 can be controlled.

4 is a known welding power supply device. The device 4 is equipped with a spool 4a wound with a consumable electrode TW of a torch T.
It is configured such that a welding power source 4b can be connected between W and the workpiece WK.

Reference numeral 5 denotes a known computer 5 which serves as a control means for the entire embodiment. Computer 5 includes a CPU and memory.

Then, a power source 4b is connected to the path line B of the computer 5.

The pass line B is further connected to the X-axis servo system aX of the robot R. The servo system Sx has X-axis power M x
s includes an encoder Ex that outputs the position information. Similarly, the pass line B is connected to a y-axis servo system 81% two-axis servo system Szs, a β-axis servo system Sα, and a β-axis servo system Sβ.

RE is a remote control panel and is provided with a group of manually operated snap switches SW. Then, if the snap switch for each of the x, y, and 2 control axes is pushed toward the rUJ side, the end effector will move in the direction in which the positional information of that control axis increases, and if it is pushed toward the rDJ side, the end effector will move in the opposite direction. . Further, the snap switches corresponding to θ and each control angle of the furnace are configured so that the torch T rotates clockwise when pushed toward the rCJ side, and counterclockwise when pushed toward the "CC" side.

The operation panel RE is also provided with a speed command rotary switch S and a mode changeover switch SM so that it can be switched to manual mode M, test mode TE, and auto mode A. SE is the repeat pattern number (
Rm) is displayed and selected. Furthermore, by setting this switch SK to the left as shown in the figure and operating switch SU, linear interpolation f L
j, circular interpolation rcJ, and comb return rRj are selected and displayed in this order.Furthermore, when switch SE is switched to the right in the figure and switch SW is operated, the welding condition number (Vla) is displayed and selected. It is being done as it should be done. tfc Furthermore, the operation panel RE is provided with a start switch ST. The function of the switch ST will be explained in detail in the explanation of the operation described later. And these switches are /(
0 JI & 7 connected to line B Note that by pressing the head of switch Sv in manual mode, the moving speed of torch T in manual mode is stored as a constant value.

The effects of the above-mentioned embodiments will be described below. Please also refer to Figure 2 and below.0 The workpiece WK has horizontal corner welding lines WLL and WL2 as shown in the figure, and these welding lines WLt and WL2
shall be attempted for horizontal fillet weaving welding.

The operator first performs teaching as follows.

(1) Operate the switch SM to set the manual mode as shown in the figure, and select the switch Sv to a speed Vm suitable for moving the torch T by manual operation (step Sl). At this time, it is assumed that the position of the torch T (the position of point P) is at the position Ro shown in the figure.
wt (welding start point of welding line WLLl:),
8 At the same time, the angle of the torch T is controlled to an appropriate posture for welding (double-dashed line in the figure) (step S2).

(3) Next, switch the switch SE to the left as shown,
Operate switch SU to select and set rLJ. In addition, switch SE is turned upward in the figure, and switch SU
to repeat the pattern number R1 (for example, 01).
Display and select. Further, operate the switch Sv to set the command speed VO for moving the torch T from R to LwI in the auto mode (step S2■■■)
.

(4) Then press switch ST (step S8)
.

(5) In response to the operation of the switch ST in step S8, the combinator 5 adjusts each axis (x, y, z) corresponding to the position and orientation of the torch T controlled in step S2■.
, θ, ψ) into memory.

In addition, the ArLJ command, repeat pattern number "Ol", and command speed V set in steps S2■ to ■
o is similarly taken into memory (step 84).

9 (6) Next, operate the switch SW to turn the torch T to the W
1 (second target point of weaving on welding line WLi)
At the same time, move the torch T upward and control the angle of the torch T to an appropriate position for welding (Step S5■)0(7) Next, switch the switch SE to the left as shown in the figure, operate the switch SU, and turn select.

Further, the switch Sv is operated to set a commanded welding speed vl for moving the torch from Ttl-Lwl to wl in the auto mode. Furthermore, the switch SE is switched to the right in the figure, and the switch SU is operated to set the welding condition (voltage, current) number Wl (for example, "lO") (step S5).

(8) Then press switch ST (step S6)
.

(9) In response to the operation of the switch ST in step S6, the computer 5 similarly scatters information on each axis corresponding to the position and orientation of the torch T controlled in step S52 into the memory. In addition, the rRJ command, welding condition number 1'lOJ, and welding speed vl set in steps S5■-■, and the repetition pattern number "Ol" set in step S2 in the bending lO are also taken into memory. (Step 57)
0 (Operate the switch SW on the spinning machine to move the torch T to the
(Welding line WL, the 8th target point of upper weaving) and at the same time control the angle of the torch T to an appropriate posture for welding (Step 58) 0 (11) Then, press the switch ST (Step S9 ).

(Similarly, the shame computer 5 takes into memory the information of each axis corresponding to the position and orientation of the torch T controlled in step S8. Also, the "R" command, the pattern number "O
1'', welding condition number ``lO'', and welding speed vl are taken into memory (step S l O).

(2) Operate the switch SW to turn the torch T to LW2.
(the welding end point of the welding line WLLi:) and simultaneously control the angle of the torch T (step 811).

(IIO also operates switches SK and SU in the same manner as above.
11, and select rLJ (step 811■).

(■Then press switch ST (step 512)
.

((5) Similarly, the computer 5 takes into memory the information of each axis corresponding to the position and orientation of the torch T controlled in step Sll. Also, the "L" command, the pattern number "Ol", the welding condition number " lO”, and welding speed v
1 is taken into memory (step 81B).

(17) Next, operate the switch SW to retract the torch T to the illustrated position RO (Step 814■) Clear "10" and operate switch Sv to set speed VO (step 814).

(19) Then press switch ST (step 51)
5).

@) The computer 5 similarly captures information on each axis f112 corresponding to the position and orientation of the torch T controlled in step 814 into the memory. Also, the rLJ command and the command speed Vo are taken into memory (step 816).
).

@) Computer 5 at this time up to s ”f [r L
andol" or rRandoIJ, and neither of these is included this time.
It is determined that the series of teachings up to now includes a new pattern. Then, from this series of information, a series of pattern information is recalculated as a position in the local coordinate system,
This is stored separately together with rRJNl(rOl').

This calculation will be explained below. See also FIG.

That is, as shown in FIG. 8, the welding line WL of the workpiece WK
Regarding 1, when the position of each point of the repetitive weaving pattern Lw1 + w□, W□, 5w2 is taught in the absolute coordinate system xyz of robot R, the coordinates are converted to the position in the local coordinate system ξηζ fixed to this workpiece WK.

That is, s The axis is the ξ axis.

Letting M be the position transformation matrix from (xyz) to (ξηζ), then each point taught above, expressed in the (ξηζ) system, has the following relation to the position: l'w= M (ww −to ) Regarding the posture, B F layer W-1°, where w = 0 to 1 (1 is the number of points forming a pattern, which is 2 in this example, and is stored separately as t; 2), 4o is Lwl This is stored as a generalized pattern of 6 and 9, which is the position of .

In order to determine the sign of the η-axis during playback, that is, the direction of generation of the weaving pattern at the same time as 1'w, find the relationship between the torch T and the straight line Lwl 5w2 □ The attitude of the torch T at Lwl is the Euler angle (θψ) Therefore, the direction cosine of the torch T and the direction cosine of the torch T are: shall be.

Therefore, the vector product jx rG is as shown in FIG. In the case of welding, this has an important meaning because the welding result will be better if the torch T is pointing downwards, and the size of the two-axis direction of T Store the coefficient a of

To explain this coefficient a in more detail, let the direction cosine of the torch T be α (α, β, γ),
Lwl 5w2 (JP2-Fl) = (Δengineering, Δ7
．． Δl), then AI'5 = i(ΔγT−Δβd)+7(nowαT−ΔXγT)+
艮(ΔworkβT−ΔyγT), that is, (ΔworkβT−Δ71T) becomes the number of threads.

At the same time, the pitch Lw1w concavity of the repeating pattern is memorized. In this case, wB is taught as a repeated pattern and is the position of the fc final point (W2 in this embodiment).

(22) Next, the operator controls the position and orientation of the torch to the position of the starting point Lw11 of the welding line WL where the same repeating pattern is desired to be executed (step 818).

(2) Furthermore, a similar repeating pattern number "Ol" is set (step 818 (2)).

(24) Then press switch ST (step S1
9).

(The computer 5 of No. 2 similarly takes into memory the information of each axis corresponding to the position and orientation of the torch T controlled in step 81716. Also, the rLJ command, the number "
"Ol" and the command speed VO are taken into memory (step 520).

(26) The operator controls the position and attitude of the torch to the end point I of welding line WL2, w12 (step S
21 ■) 0 (27) Furthermore, set the welding condition number "10" and speed ■1 corresponding to the same repeating pattern (step 821 ■) 0 (2) Then press the switch ST (step 522
).

(9) Similarly, the computer 5 takes into the memory information on each axis corresponding to the position and orientation of the torch T controlled in step S20. Also, "L" command, number "0"
1'' and [10j, as well as the commanded speed vl, are loaded into the memory (step 828).

(30) Next, operate the switch SW to retract the torch T to the illustrated position RO (step S24).

(81) Further operate switches SE and SU to
17 Return pattern number “01.J” and welding condition number “
Clear 1O. Then, the speed Vot is set by operating the switch SU (step 824).

(82) Then press switch ST (step 52)
5).

Q3B) The computer 5 similarly captures information on each axis corresponding to the position and orientation of the torch T controlled in step S29 into the memory. Further, the "L" speed command and the command speed vo are input into the mail (step 526).

In this way, the teaching of a series of user programs is completed, and the command information at each teaching point in this program is summarized in a table as shown in the following table.

It should be understood that each piece of information about the teaching points displayed on the plane 18 is stored in the pattern storage section in the memory, and the other points are stored in the step storage section. Further, the number of times the command "R" is issued, in this case "2", is stored in the memory as a value of "1-t".

Next, switch SMt is operated to set the test mode, and a known test is executed, and if there is a mistake in the program, it is corrected.

Then, by operating the switch SM to set the automatic mode and operating the switch ST, repeat pattern welding is automatically executed by the following steps.

(84) First, the computer 5 uses the system program stored in the small memory section of its memory to
Step information of the program to be executed next is loaded (step 527).

(85) It is determined whether the contents of this information include the command rLJ and the repetition pattern number (r01J in this case) (step 828).

(36) If it is included, load the step information of the program to be executed next (step 529).
).

(87) Then, it is determined whether the command rLJ and the repetition pattern number 1' 01 j are included in the contents (step 580).

(support)), calculate the number of repetitions n (step 581) 0, that is, n = ((Lvrl Lw2 /Lwl wN+
0.5)) However, j is a Gauss symbol.

(39) If not included in step 828 and S a O, the repetition ends.

(4) Following step S81, information on the weaving start point Lwl is first loaded as the position information *m(X+'l+Z+θ, ψ) of the dividing point within the linear interpolation (step 582).

(41) Then, set the values of W and m in memory to “O”
(step 833).

(42) and the incremental path (x, y, z.

θ, ψ) (step 534). At this time, the signs of the coefficient of 1 are made to match between f x Lwl Lw2 during teaching and T' x f when playing in auto mode. Determine the sign of the η-axis.If the inverse transformation matrix at that time is M'', then i w = M-1'w (ξ, η, ζ
) Regarding the posture, jw−XiaW(θ, ψ).

(48) If ko'wtl- has been obtained, calculate the point considering this increment, koW=4m+4w (step 535
).

In other words, 21 consideration W = ηm + 4'w (however, w = 0 ~ t) is (x
This is the new command value to be given in the yz) system.

(44) Then, output the value of this given W as a command value (
step 886).

(45) Next, set w w w +1 (step 587
).

(46) Then, it is determined whether w = l (step 888) 0 (47) If so, it means that one cycle of repetition has been completed, and sm = m + 1 (step 589).

(48) If not in step 88g, step S
Return to step 84 f) and repeat until vr=t.

λ (49) Following step S89, calculate the linear interpolation point value (step 540) o The method of obtaining the position information of this linear interpolation point is well known as disclosed in the aforementioned Japanese Patent Laid-Open No. 58-14189. 0 (Determine whether m-=n in the 50th order (step 841)
0 22 (51) If so, it means that all interpolation has been completed, and GiW is set as 4m (step 542).

(52) After that, ¥W is output as the command value (step 84 B), and the process returns to step 829.

■ If not in step 841, set W = 0 (step 844) and return to step 884. In this way, if it is only possible to repeat weaving from point Lwl to Lwz on welding line WLI. First, weaving can be performed in the same pattern from point LwH to LWLI at other welds 111WL2J:.

In the above embodiment, the end point of one cycle of the weaving pattern is not particularly taught, and only r - is LW.
The point on the line WL that is away from I (linear interpolation internal division point) is the end point of one cycle 7'C.

In addition, the end point of this l cycle may also be taught. Further, the repeating pattern is not limited to weaving, and is also effective when performing tack welding, for example. Namely.

A28 In Fig. 5, point LWI on welding line WL of workpiece WK
With LW2 as the starting point and LW2 as the end point, teach each point of Tsukasa and wl, however, in wl, welding condition setting, W
If it is not set in 2, tack welding will be done at point Lw.
It will be understood that it is possible to repeat the execution up to z. Furthermore, even if the robot is in a coordinate system other than the rectangular coordinate system, it can be implemented as in the above embodiment by converting the coordinates to rectangular coordinates. Furthermore, the degree of freedom at the wrist of the tip of the robot may be other than the above embodiments as long as the processing tool can take Euler angles θ and ψ. In addition, to store the repetition information of one cycle, instead of using the information taught during teaching using the workpiece, for example, the repetition patterns are standardized into several types, and these standardized patterns are
The ηζ system may be stored in advance.

Further, in all of the above embodiments, the tool serving as the end effector was a welding torch. In addition to this, for example, automatic cutting of pattern repeating cutting lines with a cutting robot equipped with a plasma cutting torch, automatic painting with an FC painting robot equipped with a painting gun to repeatedly paint the same pattern, and assembly work with an assembly robot (e.g. bolt (tightening) - Automatic assembly in which the same pattern position is repeated, etc. can also be implemented.

Other replacements of each component with equivalents within the scope of the technical idea of this invention are also included within the technical scope of this invention.

As described above, this invention has the unique and remarkable effect of being able to automatically repeatedly execute a pattern on any straight line by simply storing a pattern to be repeated in advance.

[Brief explanation of the drawing]

Figures 1 to 4 show one embodiment of the present invention.
The figure is an overall view, FIGS. 2 and 4 are flowcharts, and FIG. 8 is an explanatory diagram of the operation. FIG. 5 is an explanatory diagram of a repeating pattern in another embodiment. RO゛°Robot, 5...Computer, S 170
．． . A25 first storage means, S4, 81g, S20 and S28.
...Second storage means, 884, 885 and S86...
・Repetition means, T...welding torch (processing tool) 0 applicant
Agent for ShinMaywa Industries Co., Ltd. Tadashi Bengami (and 1 other person) Continued from page 10 Inventor Hirotoshi Yamamoto Inside ShinMaywa Industries Co., Ltd. Development Center, 6-107 Takkino-cho, Nishinomiya City0 Inventor Hisahiro Fukuoka ShinMaywa Industries Co., Ltd. Development Center, 6-107 Takkino-cho, Nishinomiya City 0 inventors Takahiro Asano 6-107 Takkino-cho, Nishinomiya City ShinMaywa Industries Co., Ltd. Development Center 0 authors Ken Kuwabara Shin Takarazuka City Meiwacho 1-1 ShinMaywa Industries Co., Ltd. Mechanical Plant Factory

Claims (1)

[Scope of Claims] (1) An industrial playback robot equipped with a processing tool as an end effector, a first storage means for storing local coordinate system information of a pattern to be repeated identically on a straight line; A second storage means for storing information on a starting point and an end point of a straight line on which the pattern is to be repeated, and a repeating means for repeating the pattern between the starting point and the end point based on the stored information in these storage means. , the industrial robot. (2) The industrial robot is a Cartesian coordinate robot. An industrial robot according to claim 1. (8) The industrial robot has a unique coordinate system other than a rectangular coordinate system, and includes means for converting this coordinate system into a rectangular coordinate system. The industrial robot described. 2. (4) The industrial robot according to claim 1, wherein the processing tool is a welding torch, and the repeating pattern is a weaving welding pattern. (5) The industrial robot according to claim 1, wherein the processing tool is a welding torch, and the repeating pattern is a tack welding pattern.