A machine tool is configured to machine a workpiece by rotating a tool and/or the workpiece. The machine tool includes a natural frequency changing unit configured to change a natural frequency before machining or during machining in the tool or a supporting portion supporting the tool.

A system comprising a processor, a non-transitory memory, and an application stored in the non-transitory memory is provided. The application is configured, upon execution by the processor, to cause the processor to generate a first controller signal based on a first set of feedback from an electric motor, based on a characterization tone, and based on a controller gain, to provide the first controller signal for operation of the electric motor, to generate a frequency response analysis on a second set of feedback from the electric motor in response to the first controller signal, and to determine a new value of the controller gain based on the frequency response analysis.

A system comprising a processor, a non-transitory memory, and an application stored in the non-transitory memory is provided. The application is configured, upon execution by the processor, to cause the processor to generate a first controller signal based on a first set of feedback from an electric motor, based on a characterization tone, and based on a controller gain, to provide the first controller signal for operation of the electric motor, to generate a frequency response analysis on a second set of feedback from the electric motor in response to the first controller signal, and to determine a new value of the controller gain based on the frequency response analysis.

A system comprising a processor, a non-transitory memory, and an application stored in the non-transitory memory is provided. The application is configured, upon execution by the processor, to cause the processor to generate a first controller signal based on a first set of feedback from an electric motor, based on a characterization tone, and based on a controller gain, to provide the first controller signal for operation of the electric motor, to generate a frequency response analysis on a second set of feedback from the electric motor in response to the first controller signal, and to determine a new value of the controller gain based on the frequency response analysis.

A system comprising a processor, a non-transitory memory, and an application stored in the non-transitory memory is provided. The application is configured, upon execution by the processor, to cause the processor to generate a first controller signal based on a first set of feedback from an electric motor, based on a characterization tone, and based on a controller gain, to provide the first controller signal for operation of the electric motor, to generate a frequency response analysis on a second set of feedback from the electric motor in response to the first controller signal, and to determine a new value of the controller gain based on the frequency response analysis.