Polar Coordinates - Siemens SINUMERIK 828D Operating Manual

Creating a ShopTurn program
8.4 Fundamentals
Incremental dimensions (INC)
With incremental dimensions (also referred to as sequential dimensions) a position
specification refers to the previously programmed point, i.e. the input value corresponds to
the path to be traversed. As a rule, the plus/minus sign does not matter when entering the
incremental value, only the absolute value of the increment is evaluated. For some
parameters, the plus/minus sign specifies the traversing direction. These exceptions are
identified in the parameter table of the individual functions.
Figure 8-8
The position specifications for points P1 to P4 in incremental dimensions are as follows:
P1: X12.5 Z-7.5 (relative to the zero point)
P2: X7.5 Z-7.5 (relative to P1)
P3:X0 Z-10 (relative to P2)
P4: X10 Z-10 (relative to P3)
8.4.4

Polar coordinates

You can specify positions using right-angled coordinates or polar coordinates.
If a point in a workpiece drawing is defined by a value for each coordinate axis, you can
easily input the position into the parameter screen form using right-angled coordinates. For
workpieces that are dimensioned with arcs or angular data, it is often easier if you input the
positions using polar coordinates.
You can only program polar coordinates for the functions "Straight circle" and "Contour
milling."
The point from which dimensioning starts in polar coordinates is called the "pole".
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Incremental dimensions
Operating Manual, 01/2015, 6FC5398-8CP40-5BA2
Turning