Determining the rigidity of a drivetrain of a machine, in particular a machine tool or production machine

A numerical controller for closed-loop control of a movement of a machine component of a machine moving along a linear guide, said numerical controller being configured to

• impart during an acceleration phase on a rotary motor having a first position sensor and being operatively connected to a linear screw drive which moves the machine component a constant acceleration on the machine component;
• measure during the acceleration phase with the first position sensor on the motor a first position of the machine component;
• measure simultaneously during the acceleration phase with a length-measuring system operably connected to the linear guide a second position of the machine component along the linear guide;
• determine a difference between the first position and the second, postion;
• form a value pair composed of the determined difference and the constant acceleration or a force producing the constant acceleration;
• and
• store the value pair and/or a rigidity value derived from the value pair.

A machine, comprising:

• a machine bed;
• a machine table;
• a linear guide secured to the machine bed and guiding the machine table along the machine table;
• a length-measuring system operably connected to the linear guide for measuring a first position of the machine component relative to the machine bed;
• a drivetrain comprising a screw drive which converts a rotational movement of a rotating motor into a translational movement of the machine table;
• a motor-measuring system comprising a motor sensor which determines from a known transmission ratio of transmission elements of the drive train a second position of the machine table in relation to the machine bed;
• and
• a numerical controller configured to impart during an acceleration phase a constant acceleration on the machine component along the linear, measure during the acceleration phase simultaneously the first position and the second position, and determine a difference between the measured first position and second position, associated the difference with the constant, acceleration or with a force producing the constant acceleration, and store a value pair composed of the determined difference and the constant acceleration or and/or a rigidity value derived from the value pair.