Kuka robot krc4 controller process of user request

Hello guys,

I’m using a kuka robot with krc4 controller kss version 8.5.4, i’m doing a machine tending application where the robot will feed a cnc machine from 2 drawers for each drawers i’m using nested for loops, i want to implement user acess request routine like when robot is working (picking the part) on drawers 1 or 2 and the user press a push button then robot will drop the part that working on it and instead to go picking next part i would like to return at home position then the user can go inside cell and when the user finish he can press start button and robot continue the operation. I don’t know if an interrupt could be a good choice for that?

Thanks in advance

Quote from SkyeFire

It depends on what you want to accomplish. If you want instant response, then an Interrupt is the way to go. But that means that you will have to have a safe "interrupt path" programmed for everywhere along your regular path, to ensure you don't hit anything.

The simpler approach would be to select certain points along your production path to be "branch points", and add IF/THEN statements at those branch points that check the inputs, and change behavior based on the inputs.

ok like on my interrupt routine i can check if robot inside cnc or outside and based on that i can create a safe path when robot inside cnc (of course i should check my gripper, my check chuck ext) and depend which zone i can add safe path to home postion and then once user is out of cell he can press a button then the robot will resume operation i will try something and get back to you if i have a question

Quote from panic mode

I would keep that simple ... let robot stay on programmed path...

When user presses request button, set a bit to remember request. Turn on light to let user know thar request is pending.

In your loop find convenient place where robot goes home or has clear path to hone

At that place add check if requested access is pending. If so move to home position and wait for access to take place and complete.... For example to confirm that access us taking place, check if user safety is tripped. Save that as access i.n progress. When access i. In progress is set but user safety is cleared, reset everything related to access request and resume cycle

i started how i will implement it, i attached picture below for better understading. My program drawer 1 is the robot start at home then will open drawer1 and he will feed cnc machine, when all part are machined then he will close drawer1 and go back home and then do samething with drawer2 (when robot working on drawer1 or 2 he will go back home once part on drawers are done) thats why i didn't find a good place to add check home inside drawer 1 or 2 routine. i don't want to check my home until drawer is closed because its take a time for it. i attached second picture for better understanding how my drawer1 or 2 works

sec image

Quote from hermann

First thing you have to do is to change your drawer programs to a different logic. As Skyefire and panic_mode already told on this thread RE: KRC4.

You should use the solution of Skyefire with the counter, not the nested loops, otherwise you will run Into problems after restarting.

Second: in the interrupt only set a flag and use return instead of resume. In main program check for the flag in appropriate places , if flag is set, go to home.

Hello Herman,

Normally is the same kind of logic between the counter or nested loop each time you will increment your counter or for loops until you reach you max on x and y. I do love want to know why counter will be advantage for user request ? But i will try it to see difference

Quote from hermann

SkyFire already told.

You use:

Code

For Column=1 to 4
 for Row=1 to 9
  ...
 endfor
endfor

Read SkyFires post in thread mentioned above. He uses xCounter and YCounter.

Now think about interrupting normal flow by user to fix something in cell in the middle of your nested loop in comparison to counters.

When you reset the program and start from beginning the loop begins from first part. The counter version begins with actual part. That's the difference. But that has been already told by SkyFire.

Now I catch what you mean, i test it with counter it work, tomorrow i will try to implement the logic of user request. I will share the news tomorrow thanks again