Siemens SINUMERIK 840D sl Programming Manual page 728

Work preparation
3.11 Collision avoidance with kinematic chains
Function properties:
● The clearance calculation is performed independent of the protection area status (activated,
deactivated, preactivated).
● To calculate the clearance of two protection areas, only protection area elements are used,
which are marked with $NP_USAGE = "C" or "A". Protection area elements of the protection
area, which are marked with $NP_USAGE = "V", are not taken into consideration.
● Protection areas, where all protection area elements of the protection area are marked with
$NP_USAGE = "V", cannot be used for the clearance calculation.
● The clearance calculation is performed with the positions valid at the end of the previous
block.
● Overlays that are included in the main run calculation (e.g. DRF offset or external zero
offset) are included in the clearance calculation with the values valid at the
function interpretation time.
Note
Synchronization
When using the PROTD() function, it is the sole responsibility of the user to synchronize the
main run and preprocessing, if required, with the STOPRE preprocessing stop.
Collision
If there is a collision between the specified protection areas, the function returns a clearance of
0.0. There is a collision if both the protection areas touch or intersect each other.
The safety clearance for the collision check (MD10622 $MN_COLLISION_SAFETY_DIST) is
not taken into account in the clearance calculation.
Syntax
[<RetVal> =] PROTD([<Name_1>],[<Name_2>],VAR <Vector>[,<System>])
Meaning
PROTD:
<RetVal>:
<Name_1>,
<Name_2>:
728
Calculates the clearance of the two specified protection areas.
● Must be alone in the block.
Function return value: Absolute clearance value of the two protection areas or 0.0
with collision (see above: Collision paragraph)
Data type: REAL
Range of values: 0.0 ≤ x ≤ +max. REAL value
Names of the two protection areas whose clearance is to be calculated (optional)
Data type: STRING
Range of values: Parameterized protection area names
Default value: "" (empty string)
If no protection areas have been specified, the function calcu‐
lates the current smallest clearance from all the activated and
preactivated protection areas in the collision model.
Programming Manual, 12/2019, 6FC5398-2EP40-0BA0
NC programming