Aborting the cell program and reloading it.

Good morning,
I am interfacing a Kuka robot with a PLC. I would like to be able to restart the Cell program in case of an emergency or just want to start over. I would like to be able to restart the Cell program in case of an emergency or just want to start over. I have one solution that is based on an interrupt and it looks like this. I found in one topic that someone does it similarly and for him to work. Here's code for my solution. Please do not judge not using Kuka's PGNO mechanism to inflict programs. This is the universal standard of my company that we use to handle robots of different companies.

Quote

DEF CELL ( )

INTERRUPT DECL 1 WHEN InSig_bRestart == TRUE DO CellInterrupt()
INTERRUPT OFF 1
WAIT SEC 0.012
INTERRUPT ON 1
WAIT SEC 0.012
    
labelStartMain:
   
MainCell()
   
   GOTO labelStartMain
   
END

DEF MainCell()
labelStart:
   
IF InSig_bExecute THEN
      
SWITCH InSig_nActionNumber ; Select with Programnumber
         
CASE 10
P10_BaseCheck()
            
CASE 20
P20_ClampsCheck()
            
CASE 30
P30_Welding()
            
CASE 40
P40_Cleaning()   
            
CASE 100
P100_Homing()
            
CASE 110
P110_ServicePos()   
            
CASE 120
P120_DisassemblyPos()
            
CASE 130
P130_TcpCheckPos()
            
CASE 140
P140_VisionCheck()  
            
CASE 150
P150_Cleaning()      
            
DEFAULT
            GOTO labelEnd
            
ENDSWITCH
      
WAIT FOR InSig_bExecute==FALSE
OutSig_nActionNumber = 0
      
labelEnd:
      
ENDIF
   
OutSig_bDone = FALSE
OutSig_bBusy = FALSE
OutSig_nActionNumber = 0
   
WAIT SEC 0
      
   GOTO labelStart

END


GLOBAL DEF CellInterrupt()
INTERRUPT OFF 1
   BRAKE
INTERRUPT ON 1
WAIT SEC 0.1
   RESUME
END

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This solution works very well when the robot is in some sub program such as p10. It restarts the program and I can start working again. But only when we have MoveEnable signals etc. given, that is, the robot is in external automation mode. But what if I don't have these signals. There is a situation that the automatic mode of the machine from the PLC level is turned off which means the robot, also does not have the automatic on. I want to be able to restart Cell when I don't have MoveEnable, ExtStart etc signals. How to make the interrupt active when the robot is not running? Maybe the MoveEnable signal alone without DrivesOn and ExtStart is enough? Is the only option left is to restart the program from SPS with CWRITE commands(STOP>CANCEL>RUN)?

 ;Restart cell.src
 IF InSig_bRestart AND NOT sps_bRestart THEN
	sps_bRestart = TRUE
 ENDIF
 IF NOT InSig_bRestart THEN
	sps_bEndRestartSeq = FALSE
 ENDIF         
 IF sps_bRestart AND NOT sps_bEndRestartSeq THEN
	CWRITE($CMD,s,m,"STOP 1")
	WAIT SEC 0.1
	CWRITE($CMD,s,m,"CANCEL 1")
	WAIT SEC 0.1
	CWRITE($CMD,STAT,MODE,"RUN /R1/CELL()")
	WAIT SEC 0.1
	sps_bRestart = FALSE
	sps_bEndRestartSeq = TRUE            
 ENDIF

I'm testing this in KukaSIM, but it doesn't work. The simulation stops after a stop, and further when I start it again, the Cell does not restart and the program continues.

Thank you all for you answers.

Quote from Leon

Not possible, MoveEnable,DrivesOn and Extstart are necessary to be able to start.

Okay, I just needed confirmation that these signals needed to be there for the interrupt to work. I was hoping there was a chance that this interrupt could work "somehow in the background".

Quote from Leon

which program continues if cell is stopped? How is cell stopped? why isn't it looping and waiting for commands from the PLC?

I am testing my program in KukaSIM. I set the active program Cell.src and Submit SPS is running in the background. When I force RESTART simulating PLC. Sps responds to this, the STOP 1 command is executed and the simulation pauses. When I resume the simulation, the program lines in SPS fly through, i.e. CANCEL 1 and RUN CELL.src. But the simulation continues from the place where the STOP 1 command was triggered. The Cell.src program does not start from beginning and does not loop in this program waiting for the bExecute signal. It only continues to work in the program in which STOP 1 occurred, i.e. P10. Perhaps this is related to the fact that I am testing it in KukaSIM and not on a real controller or at least OfficeLite?

Quote from Leon

It is possible, the question is it necessary? If have been through your post several times and i have still trouble understanding what happened to the robot that you have to restart Cell.

I think I have developed this issue above. After the unpause, the robot continues to work from the place where STOP 1 occurred.

Quote from Leon

Also it would be nice if you mention what type of controller you are working with (KRC2,KRC4 or KRC5) with the KSS version as stated in the "Read first" topic.

Currently I don't have the robot with me yet, I'm preparing the entire project offline for now. But the controller will be KRC5 and I think it will be version KSS 8.7

Quote from panic mode

This 'solution' is done by someone not concerned with things like cost, downtime, collisions... There is ZERO validation if called program number is really correct. in other words this is a time bomb. single corrupt bit or loose I/O wire can result in calling wrong program and when that happes it will be a big and expensive mess. sure it works now but give it time...

All of this is managed by the PLC controller. In our applications, it assigns the program to the robot based on many conditions. The robot in our applications is a regular tool, such as a servo drive. I give it a program number and a start command, and the robot, being in program P10, for example, returns number 10 to me, and I, on the PLC controller side, know about it. The robot executes the program and returns the DONE status to me and waits until I turn off the bExecute signal. Like an ordinary MoveAbsolute movement in a servo drive.

Quote from panic mode

you mean robot can continue working.

Yes, I meant the robot. The Cell program is restarted/The program pointer is in Cell.src and not in the Subprogram and waits for a signal from the PLC controller which program should be executed again and the bExecute command.

Quote from panic mode

So...?

The thing is that the interrupt solution won't work and I guess I have to handle it in SPS.

Quote from panic mode

What do you mean by "restart Cell"? robot program CANNOT run when move enable is false - that is by design. If you want to be able to select and run CELL (or whatever program) in other modes, you need to evaluate application needs and adapt PLC code, because that is what controls move enable. one common case is use of T1 to test and modify programs so normally move enable SHOULD be true when robot is in T1 mode.

Sure, I understand, here I only meant to outline the situation in which I need to restart the Cell.src program, so that the program pointer loops and waits again for the program number from the PLC and the bExecute signal. I simply want the robot not to be in any subprogram after my restart, but for the Cell.src program to be loaded again. But without giving it the MoveEnable, DrivesOn and ExtStart signals. So everything then comes down to handling it in the SPS.

Quote

Someone wrestling with basic things like move enable, Drives on etc is not qualified to PROGRAM robots... And certainly should NOT be allowed to mess with advanced concepts such as use of interrupts.

I will leave this without comment.

Quote

No it is not. One of the options is to manually select the program. in fact standard CELL.SRC that KUKA supplies in form of a template is meant for just that - manually select and start CELL program until robot is at home and BCO is done, THEN change mode to EXT and let PLC take over. and once it runs it should NEVER need deselecting of CELL.src. what kind of "emergency situations" you are running into that require reseleting of your CELL?

This solution is not for me. I need to be able to remotely start the Cell.src program from beginning. I have several robots in my applications and I can't imagine going to the robot teachpedant/smartpad and selecting the Cell.src program on each one after a certain situation. For me, as a programmer responsible for starting the entire line, the robot is one of many subsystems that has to perform a task and return a signal that it has completed the task. Depending on the machine, the robot manufacturers often change and each robot has a different control, so please don't tell me that I shouldn't start programming robots because I've already started more than one. I just wanted to ask about certain issues, because everything happens differently on each robot.


To sum up all my ramblings. I wanted to restart the Cell.src program - that is, for the robot to exit all sub-programs and the Cell.src program to load again with the program pointer in line 0. All this was to take place without giving the MoveEnable, DrivesOn, ExtStart signals. Only then does the superior PLC controller start the automatic cycle of the entire machine and the robot receives the MoveEnable > DrivesOn > ExtStart signals accordingly. And only then does the PLC controller give it the program number to execute and the bExecute signal to start for example program P10. And I wanted to get confirmation whether doing this from the SPS level with the commands: STOP 1, CANCEL 1 and RUN Cell.src will achieve this. And additionally, get the answer that testing this in KukaSIM has certain limitations and it may not work entirely.