Patent ID: 9444385
Filing Date: 2016-09-13
CPC Classification: H02N,H02P

Claim Text:
1. A control apparatus for a vibration type actuator, comprising: a command unit which gives a command indicating at least one parameter selected from the group consisting of frequency, amplitude, and phase at an AC voltage; a variable adding unit which adds a signal or noise to the command output from the command unit selected from the group consisting of a sine wave signal and a pseudo random number signal as the signal, and white noise as the noise; an AC voltage generator which generates the AC voltage based on the command output from the command unit and the signal or the noise output from the variable adding unit; a frequency response characteristic measuring unit which receives as an input the signal or the noise output from the variable adding unit and a physical quantity varying with vibration of a vibrating member and obtains a frequency response characteristic at one or more frequencies; a resonance frequency estimation unit which estimates a resonance frequency of the vibrating member from the frequency response characteristic obtained by the frequency response characteristic measuring unit; and a frequency range limiter which determines a frequency range for the AC voltage output by the AC voltage generator according to an estimated value for the resonance frequency output from the resonance frequency estimation unit.