If it is just for machine safety not human safety then you could use a combination of DCS and BG logic.
DCS could be a less restrictive sized cube, maybe with the corners knocked out by DCS out zones.
Then you could use BG logic to monitor the sum of squares of the current position and ensure it is below a certain limit or trigger a hold or stop signal.
I liked the idea of creating a "poor man's" spherical world zone.
Here it is:
/PROG POORMANS_WZ
/ATTR
OWNER = MNEDITOR;
COMMENT = "In Sphere?";
PROG_SIZE = 733;
CREATE = DATE 25-02-10 TIME 16:20:56;
MODIFIED = DATE 25-02-10 TIME 16:20:56;
FILE_NAME = ;
VERSION = 0;
LINE_COUNT = 20;
MEMORY_SIZE = 1057;
PROTECT = READ_WRITE;
TCD: STACK_SIZE = 0,
TASK_PRIORITY = 50,
TIME_SLICE = 0,
BUSY_LAMP_OFF = 0,
ABORT_REQUEST = 0,
PAUSE_REQUEST = 0;
DEFAULT_GROUP = *,*,*,*,*;
CONTROL_CODE = 00000000 00000000;
LOCAL_REGISTERS = 0,0,0;
/APPL
/MN
1: !Sphere Location (World): ;
2: ! X,Y,Z: ;
3: R[11:Sphere X]=(1431) ;
4: R[12:Sphere Y]=(-506) ;
5: R[13:Sphere Z]=(542) ;
6: !Sphere Radius: ;
7: R[14:Sphere Radius]=(300) ;
8: !Current Position of ;
9: ! the active TCP in World. ;
10: ! X,Y,Z: ;
11: R[15:Curpos X]=($SV_INFO[1].$CART_POS[1]) ;
12: R[16:Curpos Y]=($SV_INFO[1].$CART_POS[2]) ;
13: R[17:Curpos X]=($SV_INFO[1].$CART_POS[3]) ;
14: !Calc dist ^2 ;
15: R[18:Dist^2]=(((R[11:Sphere X]-R[15:Curpos X])*(R[11:Sphere X]-R[15:Curpos X]))+((R[12:Sphere Y]-R[16:Curpos Y])*(R[12:Sphere Y]-R[16:Curpos Y]))+((R[13:Sphere Z]-R[17:Curpos X])*(R[13:Sphere Z]-R[17:Curpos X]))) ;
16: IF (R[18:Dist^2]<(R[14:Sphere Radius]*R[14:Sphere Radius])) THEN ;
17: F[1:In Sphere]=(ON) ;
18: ELSE ;
19: F[1:In Sphere]=(OFF) ;
20: ENDIF ;
/POS
/ENDI tested it, and it works. I initially tried using local registers to do it, but it looks like background logic does not like them
