[Treva]

Hi,
I'm comparing NC codes about FANUC, Siemens and Heidenhain for the simultaneous 5-axis machining.
RTCP is different with TCPM?
I'm confusing.
In some CAM manual that ESPRIT 2009 it was discribed that they are same.
Names are only different. (FANUC G43.4, Heidenhain M128 and Siemens TRAORI)
But I wonder there are different or not.
Even though it's for Heidenhain controller manual has same figure with other two controllers in manuals but Heidenhain(iTNC-530) manual was discribed that it is improved from RTCP (M128) to TCPM(M91).
Is that right?
Do you know the difference of RTCP and TCPM?
Let me know that differences please.

[Alan L]

Generically speaking they are the same. But the actual performance of these functions is not in a manual, but inside the software/firmware of the control manufacturers. And they don't seem to tell you exactly how they accomplish the mathematics for tool center point control.

There are a few different functions that may be included in the "tool center point" technology concepts.

1. Kinematic transformations (multi-axis) are performed inside the CNC control. A benefit of this is that the CAM software postprocessor need not perform this math. The second benefit is that pivot offsets are held within the machine control register tables. The big benefit of this function is that one NC program can be applied to different machines in your shop that may have different pivot offsets. In the old days (not so long ago), you would have to include the pivot offsets in the CAM postprocessor, and then need different NC code to run the same part on machineA and machineB (same maker and kinematics).

Together with this, feedrate is controlled at the tool tip using math inside the control. This latter point is in contrast to historical "inverse time" modes where the CAM software had to calculate a time (feedrate) for each block.

2. Tool center point management often includes fixture offsets. A part is placed on the machine tool. The local is determined by on-board probes. The position offsets are added to the above-mentioned pivot offsets.

The benefit again is that serial parts can be put on the same machine, located by probe, and one set of NC instructions can cut all parts. The end-user need not spend extra hours "tapping" in a part so that it is located on center within an acceptably small tolerance.