Frequency characteristic measurement apparatus and frequency characteristic measurement method

A frequency characteristic measurement apparatus comprising:

• a first output part that outputs a first excitation signal in a first frequency range;
• a frequency characteristic calculator that calculates a first frequency characteristic of a servo system in the first frequency range based on the first excitation signal and a first state signal, the first state signal indicating a state quantity of the servo system and being acquired from the servo system having received the first excitation signal;
• a resonance frequency calculator that calculates at least one of a resonance frequency or an antiresonance frequency of the servo system based on the first frequency characteristic;
• a second output part that outputs a second excitation signal in a second frequency range including at least one of the resonance frequency and the antiresonance frequency calculated by the resonance frequency calculator and belonging to a partial range of the first frequency range,
• the frequency characteristic calculator being configured to further calculates a second frequency characteristic of the servo system in the second frequency range based on the second excitation signal and a second state signal, the second state signal indicating a state quantity of the servo system and being acquired from the servo system having received the second excitation signal;
• and
• a frequency characteristic synthesizer that synthesizes the first frequency characteristic and the second frequency characteristic to calculate a third frequency characteristic of the servo system in the first frequency range.