Calibration for numerically controlled machining

A method in a computing system for calibrating a tool control mechanism used by a numerically controlled (NC) machining system, the tool control mechanism including at least one rotational axis, the method comprising:

• fitting a geometric model on a set of 2-dimensional position measurements of a tool center point (TCP) rendered by the tool control mechanism, wherein individual 2-dimensional position measurements A) correspond to a respective rotational angle of at least one rotational axis and B) are not measured relative to a position of the NC machining system along non-rotational axes;
• deriving one or more offset factors with respect to a distinct rotational axis, without regard to position of the NC machining system along non-rotational axes, wherein the deriving is based at least in part on the fitted geometric model, and wherein the one or more offset factors at least partially define a kinematic model that models 3-dimensional offsets of the TCP;
• utilizing the kinematic model as defined by the one or more offset factors to determine a 3-dimensional offset of the TCP based at least in part on a specified rotational angle of the distinct rotational axis;
• and
• causing application of positional compensation to the TCP in accordance with the determined 3-dimensional offset.

A non-transitory computer-readable medium having contents configured to cause a computing system to perform a method in a computing system for calibrating a numerically controlled (NC) machining system including at least one rotational axis, the method comprising:

• fitting a geometric model on a set of 2-dimensional measurements that indicate positions of a tool under control of the NC machining system, wherein individual 2-dimensional measurements (A) correspond to a respective rotational angle of a distinct rotational axis and (B) are not relative to a position of the NC machining system along non-rotational axes;
• deriving at least one offset factor in a third dimension with respect to the distinct rotational axis and without regard to the position of the NC machining system along the non-rotational axes, wherein the deriving is based at least in part on the fitted geometric model, wherein the at least one offset factor at least partially defines a mathematical calibration model for determining compensation to a 3-dimensional position of the tool;
• and
• causing operation of the NC machining system based on the mathematical calibration model as at least partially defined by the at least one offset factor.