Cartesian Ptp Travel; Function - Siemens SINUMERIK 840D sl Function Manual

M1: Kinematic transformation

7.6 Cartesian PTP travel

7.6 Cartesian PTP travel
7.6.1

Function

Precondition
Cartesian point-to-point or PTP travel can only be activated if one of the following
transformations is active:
● Orientation transformation (TRAORI)
● Face end transformation (TRANSMIT)
● Concatenated transformation (TRACON), provided that the first concatenated
transformation supports PTP travel
Without active transformation, alarm 14146 "CP or PTP motion without transformation not
permitted" is output.
Note
The axes of the transformation must not simultaneously be positioning axes.
Function
With the Cartesian PTP travel, in G0 and G1 sets it is possible to approach a point programmed
as a Cartesian destination point with a synchronous axis movement.
Regarding the traversing movement, the Cartesian PTP travel acts as though no
transformation is active The position data in the part program continue to be in the Cartesian
workpiece coordinate system. Programmed frames (coordinate movements and rotations)
remain valid. The display is also in the Cartesian workpiece coordinate system.
The movement in the Cartesian PTP travel is described by a starting and end position of the
axes. The path of the movement described by the individual axes from the starting to the end
position is not specified by the controller by means of path interpolation points and can
therefore not be predicted. The axes only have to reach their specified target position.
Interaction between the axis movements only exists in regard to time, i.e. all axis start
simultaneously and are stopped at the same time when the target position has been reached.
The slowest axis determines the total traverse time.
One sensible usage option is to travel by a singularity. If Cartesian positions are available,
which are provided by a CAD/CAM system for example, this has the benefit of not having to
convert them into machine axis values. Furthermore, direct traversing of the machine axes is
time-optimized compared to Cartesian traversing with active transformation and programmed
feed. The result of this would either be a corresponding reduction of the feedrate when
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Function Manual, 10/2015, 6FC5397-1BP40-5BA3
Extended Functions