'zeroing' and external axis position inside a loop

AndrewZ · Jun 19th 2015

Hi, I am new to this forum and having failed to find the answer via KRC manuals or internet searches I am hopeful someone can help me with a programming problem.

I have am generating programming instruction in software for a 6 axis Kuka robot (KRC 2) that has an external axis E1. The external axis is a rotating station but is configured as a linear axis.
I very simplified example is shown below, with an initial position and a repeated loop of positions. A real example might have many hundreds of lines. Note that at the last position
in the loop all axes are back to the original position EXCEPT for E1 which continuously increases. What I need do is reset/zero/datum) E1 AT ITs CURRENT position at this last point.

example1:

LIN {X +350.000, Y +0.000, Z +400.000, A 0.000, B 0.000, E1 0.000}
HALT

FOR N_CYC=1 to 37
LIN {X +370.000, Y +5.000, Z +400.000, A +1.905, B +0.000, E1 +100.00} C_DIS
LIN {X +400.000, Y +10.000, Z +410.00, A +1.489, B +0.000, E1 +200.00} C_DIS
LIN {X +475.000, Y +20.000, Z +410.000, A +1.092, B +0.000, E1 +300.00} C_DIS
LIN {X +500.000, Y +20.000, Z +450.000, A +2.378, B +0.000, E1 +400.00} C_DIS
LIN {X +200.000, Y +10.000, Z +410.000, A +3.379, B +0.000, E1 +500.00} C_DIS
LIN {X +350.000, Y +0.000, Z +400.000, A 0.000, B 0.000, E1 +600.000} C_DIS
; I now need a way to reset E1 to the initial position e1=0.000
; before doing the next loop
ENDFOR

another way might be something like below. Yes I know the syntax shown is not valid but some suggestion along these lines that works would be good.

example2:

LIN {X +350.000, Y +0.000, Z +400.000, A 0.000, B 0.000, E1 0.000}
HALT

MYREALVAR=600.0

FOR N_CYC=1 to 37
LIN {X +370.000, Y +5.000, Z +400.000, A +1.905, B +0.000, E1=MYREALVAR*(N_CYC-1)+100.00} C_DIS
LIN {X +400.000, Y +10.000, Z +410.00, A +1.489, B +0.000, E1=MYREALVAR*(N_CYC-1)+200.00} C_DIS
LIN {X +475.000, Y +20.000, Z +410.000, A +1.092, B +0.000, E1=MYREALVAR*(N_CYC-1)+300.00} C_DIS
LIN {X +500.000, Y +20.000, Z +450.000, A +2.378, B +0.000, E1=MYREALVAR*(N_CYC-1)+400.00} C_DIS
LIN {X +200.000, Y +10.000, Z +410.000, A +3.379, B +0.000, E1=MYREALVAR*(N_CYC-1)+500.00} C_DIS
LIN {X +350.000, Y +0.000, Z +400.000, A 0.000, B 0.000, E1=MYREALVAR*(N_CYC-1)+600.000} C_DIS
ENDFOR

Any help would be most appreciated
Andrew

**panic mode** · Jun 19th 2015

I don't think that is possible.... What you may want to do is create another variable just for E1 position then do some math.

for example

Code

DEF MAIN()
DECL REAL E1


E1 = Mod360($AXIS_POS.E1)


 ;.... do whatever


END

Display More

Where Mod360.src is something like this:

Code

DEFFCT REAL Mod360(x1:in )
  DECL REAL x1,result
  DECL INT n1
  n1=x1/360          ; division and casting to integer
  result = n1*360    ; compute part to be removed
  result = x1-result ; and now remove it
  if result<0.0 then ; check if it is on [0,360]
     result = result + 360.0 ; and correct if needed
  endif
  RETURN (result)    ; return value
ENDFCT

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**SkyeFire** · Jun 20th 2015

Quote from AndrewZ

another way might be something like below. Yes I know the syntax shown is not valid but some suggestion along these lines that works would be good.

example2:

LIN {X +350.000, Y +0.000, Z +400.000, A 0.000, B 0.000, E1 0.000}
HALT

MYREALVAR=600.0

FOR N_CYC=1 to 37
LIN {X +370.000, Y +5.000, Z +400.000, A +1.905, B +0.000, E1=MYREALVAR*(N_CYC-1)+100.00} C_DIS
LIN {X +400.000, Y +10.000, Z +410.00, A +1.489, B +0.000, E1=MYREALVAR*(N_CYC-1)+200.00} C_DIS
LIN {X +475.000, Y +20.000, Z +410.000, A +1.092, B +0.000, E1=MYREALVAR*(N_CYC-1)+300.00} C_DIS
LIN {X +500.000, Y +20.000, Z +450.000, A +2.378, B +0.000, E1=MYREALVAR*(N_CYC-1)+400.00} C_DIS
LIN {X +200.000, Y +10.000, Z +410.000, A +3.379, B +0.000, E1=MYREALVAR*(N_CYC-1)+500.00} C_DIS
LIN {X +350.000, Y +0.000, Z +400.000, A 0.000, B 0.000, E1=MYREALVAR*(N_CYC-1)+600.000} C_DIS
ENDFOR

Any help would be most appreciated
Andrew

Display More

Simple enough.

Code

FOR N_CYC = 1 To 37
  NextPos1 = {X +370.000, Y +5.000, Z +400.000, A +1.905, B +0.000}
  NextPos1.E1 = MyRealVar * (N_CYC-1) + 100


  NextPos2 = {X +400.000, Y +10.000, Z +410.00, A +1.489, B +0.000}
  NextPos2.E1 = MyRealVar * (N_CYC - 1) + 200


  ; and so on


  LIN NextPos1 C_DIS
  LIN NextPos2 C_DIS
  ;and so on

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Fubini · Jun 20th 2015

Or if you have a newer KRC4 simply

SPTP_REL {X +350.000, Y +0.000, Z +400.000, A 0.000, B 0.000, E1 -<Your starting angle>}

For relative spline movements the KRC does no longer use modulo 360 degrees.

Fubini

AndrewZ · Jun 22nd 2015

Thanks for your comments guys.
Something along the lines of SYKFIRE's post is what I will tryout. It is rather a shame that it seems not possible to make a mathematical assignment to an element (axis) within a line of motion such as a LIN. We thus need three lines of code for each position (define, modify, move) which makes the program far less readable. Hayho, that's life

mayank · Jun 24th 2015

you can try one more thing you can make the axis e1 as decouplable axis. you have to make few changes in your mada file. you can use this logic where you want to make e1 axis 0.

precondition to do this you have to change the value of variable $brk_mode to B1010 to B1101 in mada. and have to declare the axis decouplable in mada.

$async_axis='B000001' ; to make the e1 axis asynchronous

wait sec 1

$async_ex_ax_decouple= 'B111110' ;to decouple the eternal axis
$axis_act.e1=0

WAIT FOR $AXIS_JUS.E3==TRUE
$async_axis='B000001' ; to couple it again

AndrewZ · Jun 24th 2015

mayank. Interesting thanks. That will be useful for me to reset the E1 axis in some other circumstances but not in this case. The loop is a continuous motion and the axis reset would cause unwanted pauses.

12ph · Jul 18th 2019

Quote from mayank

you can try one more thing you can make the axis e1 as decouplable axis. you have to make few changes in your mada file. you can use this logic where you want to make e1 axis 0.

precondition to do this you have to change the value of variable $brk_mode to B1010 to B1101 in mada. and have to declare the axis decouplable in mada.

$async_axis='B000001' ; to make the e1 axis asynchronous

wait sec 1

$async_ex_ax_decouple= 'B111110' ;to decouple the eternal axis
$axis_act.e1=0

WAIT FOR $AXIS_JUS.E3==TRUE
$async_axis='B000001' ; to couple it again

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DEF RESET_E2()
ptp $pos_act
$ASYNC_AXIS='B00010'
WAIT SEC 0.5
$ASYNC_EX_AX_DECOUPLE='B00010'
WAIT SEC 0.5
$AXIS_ACT.E2=0
WAIT SEC 0.5
$ASYNC_EX_AX_DECOUPLE='B00000'
WAIT SEC 0.5
$ASYNC_AXIS='B00000'
END

Gives an error message:

Ackn. de-/coupling not allowed for axis E2

stops at this line: $ASYNC_EX_AX_DECOUPLE='B00010'

What's the matter?

**panic mode** · Jul 18th 2019

Use WoV to configure axis... Enable coupling

the leg · Jul 23rd 2019

OP is using KRC2 ?

**panic mode** · Jul 23rd 2019

true but my response was not to OP. and if someone chooses not to share system info, i will choose to assume platform...

the leg · Jul 23rd 2019

Quote from panic mode

true but my response was not to OP. and if someone chooses not to share system info, i will choose to assume platform...

??

12ph · Jul 27th 2019

Quote from panic mode

Use WoV to configure axis... Enable coupling

I did as you said. But I had another problem.
I could not manually move the axis E2
Look at 1st image.

I also had to change the terminals from 1 and 2 to 7 and 8. Since when I switched on the coupling in WorkVisual, they changed from 1 and 2 to 7 and 8. Look at 2nd and 3rd image.

When I go into the proposal proposal, WorkVisual wants to remove RDC. Look at video.

**panic mode** · Jul 27th 2019

[size=2]You will be banned for spamming. this is the last and only warning. R[/size][size=2]ead READ FIRST and stop hogging resources. many old topics are not longer available because of ignorance and indifference of some users.

Not only you are posting same things in multiple threads but you also duplicated attachments. [/size]
[size=2]That is countering investments and hard work of those that try to keep this place free and great resource. [/size]

12ph · Jul 28th 2019

Quote from panic mode

[size=2]You will be banned for spamming. this is the last and only warning. R[/size][size=2]ead READ FIRST and stop hogging resources. many old topics are not longer available because of ignorance and indifference of some users.

Not only you are posting same things in multiple threads but you also duplicated attachments. [/size]
[size=2]That is countering investments and hard work of those that try to keep this place free and great resource. [/size]

I am very sorry. I have to solve this problem as soon as possible.

'zeroing' and external axis position inside a loop

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