Restarting the main program

    Hi!

    I need a way to go back to eg. line 10 of the main program before the main loop starts (an alternative may be to restart the main program entirely). This also needs to work from any called subprograms.

    I have thought about the following solutions and wonder what you may consider the most proper way of doing it or if you have any input:

    One solution may be to monitor the signal in a PC program, eg.

    I feel the first alternative is kind of a hack as it resets the execution stack which I feel is unnecessary? Alternative 2 feels more proper in a way? Another solution may be to use an ONI instruction and replicate the same ONI instruction in every subprogram called from the main program.

    The problem now is that I have to remember to put ONI instructions in every subprogram. The JUMP instruction also mentions that it may not jump to the source program, but I guess by calling it from within the InterruptProgram it might work as the MainProgram is then no longer the source program.

    I am not able to test this right now so I am just asking to verify if I am on the right track or if I should do something different that is more "proper".

    Thank you very much and sorry for the long post!

    Is not mandatory to restart the program if, the robot dropped the box. You might have 2 options:

    1. The robot can continue the motions (for example there is no enough vacuum level and the box is still in the gripper, the operator placed the box in the gripper)

    2. The robot can pick another box (in this case, just make the program in such a way that the robot is able to go back at picking position)

    Quote from robocoder

    I need to be able to cancel the current task (eg. if a box is dropped) and then go back to start and grab the next box.

    I can solve the go back to line 10 by moving the lines above in a separate program (eg. initialize). then initialize calls the main program.

    There is no need to terminate the Program's Task. This is because you can exit again using Return instruction when the Sub Program is called.

    In general, forcefully terminating a task is mainly used for emergency situations such as forced homing or special event handlers. You don't need to consider it during normal automatic startup.

    ABB, FANUC, Hyundai, Kawasaki

    Quote from robocoder

    I need to be able to cancel the current task (eg. if a box is dropped)

    So where is the location of the dropped box can you ensure the following:

    - Does it interfere with further robot motion.

    - Does it interfere with other cell peripheral operations.

    - Does it prevent the next box in from getting to the picked position.

    - Does it still remain in a position to be picked again.

    Not everything is solved with automatic return to pick next box.

    At some point, someone will need to clean up the mess of dropped boxes and ask questions.

    - Why was the box dropped in the first place - can this be engineered out instead.

    Consider creating not only a pick motion subroutine only, but also a gripper activation subroutine and gripper check subroutine with 'constant loop traps'.

    This way you can create simple checks and trap inside gripper subroutines using TIMERS/UTIMERS and PAUSES.

    Remember programming is about getting the operation working, not about elegance.

    Interrupts should be carefully studied in the AS Manual as there are several flavours with differences.

    An interrupt wants to return to the point of interruption.

    Consider this in relation to signal states, but importantly for return robot paths and trajectories.

    It is easy to implement an interrupt and also as easy to neglect the return path from the interrupt and wipe things out.

    Of course, an interrupt does not have to include a motion segment, just a simple pause command will do and upon pressing cycle start again, it will return to where it was interrupted from which will be the same place and can be just as effective as 'constant loop trap routines'.

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