Safety program in Automatic mode

    I'm looking to create a safety program for when the robot operates in automatic mode.

    What factors should I keep in mind during the planning process? What potential issues could arise, and what are the best practices for safely returning the robot to its home position?:thinking_face:

    Breadcrumb mentality is good for recovery in auto from auto. You use registers basically to update where the robot was at in a program when it was stopped your recovery program sees that and knows it needs to back out of the position to a safer position then on to its "Home".

    For any recovery after manual movement, it gets much trickier as the robot doesn't really have a reference to rely on for it position or surrounding obstacles. Scara are easy though as you can send it to a known good z height and then home.


    For full safety though a risk assessment is always going to be recommended.

    Quote from ASUA1

    Breadcrumb mentality is good for recovery in auto from auto. You use registers basically to update where the robot was at in a program when it was stopped your recovery program sees that and knows it needs to back out of the position to a safer position then on to its "Home".

    For any recovery after manual movement, it gets much trickier as the robot doesn't really have a reference to rely on for it position or surrounding obstacles. Scara are easy though as you can send it to a known good z height and then home.

    Personally I would avoid the use of registers to track where the robot was. The reason is that you do not really know if someone has just moved the robot manually before executing the homing sequence.

    I would suggest to just create a few of SpaceFunctions and check these areas on the homing routine, then, knowing where the TCP is located you can guess how to move in order not to collide, or just move in one direction and then go to a reference point (you could also set reference points and check the associalted DO), then go home with a taught path.

    I've had very awful experiences with robots whose recovery paths were programmed using registers, and it makes the code very dirty if you need to know where the robot was all the time.

    Quote from Shellmer

    Personally I would avoid the use of registers to track where the robot was. The reason is that you do not really know if someone has just moved the robot manually before executing the homing sequence.

    You can use some code like this in a background logic:

    Code
    IF ($MOR_GRP[1].$JOGGED=1) OR (DO[8:TP enabled]=ON AND $MOR_GRP[1].$ROB_MOVE=1) THEN ;
!rob has been moved manually or by program in manual mode
ELSE ;
!rob has not beeing moved ;
ENDIF ;


    $MOR_GRP[1].$JOGGED
    A boolean variable, indicating that the robot has been jogged since last motion by program.
    It is reset to FALSE on program motion start.

    Keep in mind: It does not maintain TRUE state through power restart, and is always FALSE on power up.


    DO[8:TP enabled]
    A system signal indicating the TP is switched to manual mode.


    $MOR_GRP[1].$ROB_MOVE
    A boolean variable, indicating that the robot is moving (by program or by jogging).


    This code will recognize jogging the FANUC or running a motion command via program (and therefore maybe leaving the path) while in manual mode.

    Because the DO and $JOGGED are reset when switching on, the code does not (currently) recognise whether the FANUC has been moved to a different position and then switched off.

    To do this, you could save the current position on the rising edge of $ROB_MOVE and compare it with the current position after switching on(!?) This is already on my TODO list. :smiling_face_with_halo:

    Yeah, it could be a solution, but I just preffer to use the space functions as I know that the gripper is inside an area and I can know how and where to move to exit safelly. Been using this method for years and it works wonderfully, it rarelly collides and if it does, it's at a very low speed.

    I also use the reference positions to return home, and sometimes even the axis degrees or word coordinates. The homing procedure is usually structured to first check if the robot is on any refposition, then if it's on any spcfunction, then if it's on a certain zone checking by coordinates or axis values, and if everything fails... it just aborts the program and someone must move it manually.

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