The invention pertains to a device for at least one low-frequency electric tank circuit, in which at least one electric conductor is an influencing component of the tank circuit due to its properties.

A control device for a vibration actuator includes a detection signal acquisition section adapted to obtain an alternating-current detection signal corresponding to a vibration of the resonator body from the resonator bodies, a phase difference detection section adapted to detect a phase difference between the drive signal and the detection signal with respect to the resonator bodies, a resonator body selection section adapted to select one from the resonator bodies, and a drive signal control section adapted to adjust a frequency of the drive signal so that the phase difference in the resonator body selected comes closer to a target value.

A self-oscillating piezoelectric actuator drive circuit includes a integrating circuit; an inverter (INV1), inverters (INV2 and INV3) inverting an output signal of the inverter (INV1), sense resistors (Rs1 and Rs2) connected to output sides of the inverters (INV2 and INV3), a positive feedback resistor (Rfb2) feeding back an output signal of the inverters (INV2 and INV3) to the integrating circuit; and a negative feedback resistor (Rfb1) feeding back a voltage generated from the sense resistors (Rs1 and Rs2, Rs1<Rs2 in terms of a resistance value) to the integrating circuit. In a startup state, the sense resistor (Rs2) and the inverter (INV3) are selected, and in an operating state after the startup state, the sense resistor (Rs1) and the inverter (INV2) are selected.

A soft haptic device and a local control method are disclosed. The soft haptic device includes a soft actuator. The soft actuator includes an electroactive polymer film, a patterned electrode, and a dielectric liquid injected between the electroactive polymer film and the patterned electrode. The soft actuator generates a reconfigurable shape such that a form of an output shape and a number of outputtable shapes are changed depending on the number of electrodes constituting the patterned electrode, a shape of the electrodes, and an arrangement of the electrodes.

A piezoelectric actuator includes a piezoelectric element, a vibrating plate configured to vibrate according to application of a signal to the piezoelectric element, and a driven body driven by the vibration of the vibrating plate. The vibrating plate vibrates in a first mode according to a signal having a first frequency, vibrates in a second mode according to a signal having a second frequency, and vibrates in a third mode according to a signal having a third frequency. The first frequency and the second frequency are different. The first frequency and the third frequency are different.

A method for controlling an ultrasonic motor. From a starting velocity or starting position of the driven element, the method includes adjusting the frequency of the electrical excitation voltage such that it is equal to or close to the mechanical resonance frequency of the ultrasonic actuator; changing the frequency of the electrical excitation voltage using the signal of the velocity sensor or the position sensor towards the anti-resonance frequency of the ultrasonic actuator until an end velocity or an end position of the driven element is reached; and controlling the end velocity or position of the driven element with a predetermined accuracy by means of antiphase frequency change. Also disclosed is a corresponding control arrangement for an ultrasonic motor having an ultrasonic actuator with at least two acoustic wave generators, a driven element and a generator via a frequency adjustment.

A semi-resonant actuator assembly includes a resonating body comprising a piezoelectric plate having a first length, a first width, and a first thickness, and an inactive plate having a second length substantially equal the first length, a second width substantially equal to the first width, and second thickness. A thickness of the resonating body is provided by a sum of the first thickness of the active piezoelectric plate and the second thickness of the inactive plate.

A driving circuit for a vibration type actuator includes an inductor and a capacitor which are connected in series to an electric-mechanical energy conversion element, in which, in a case where a series resonance frequency based on the inductor and the capacitor is set as fs, and a resonance frequency in a vibration mode other than vibration used for driving of the vibrator is set as fu, 0.73.Math.fu<fs<1.2.Math.fu is satisfied.

Provided is a method for calculating a scanning pattern of light and an optical scanning apparatus. The method includes the steps of: detecting a resonance frequency and an attenuation coefficient of an oscillation part of an optical fiber which guides light from a light source and irradiates an object with the light; and calculating a scanning pattern of the light, based on the detected resonance frequency and attenuation coefficient. The apparatus includes: an optical fiber which guides light from a light source and irradiates an object with the light; a scanning part which drives an oscillation part oscillatably supported of the optical fiber; a detector which detects a resonance frequency of the oscillation part; a calculation part which determines an irradiation position of the light using a scanning pattern calculated based on the resonance frequency detected by the detector and the attenuation coefficient obtained in advance.

A vibration motor controller controls driving velocity of a vibration motor relatively moving a vibrator and a contactor contacting the vibrator, the vibrator oscillated by an electromechanical energy transducer to which first and second frequency signals having a phase difference are applied, and includes a phase difference determiner storing a relationship between the frequency and phase difference between the first and second frequency signals, and determines the phase difference with respect to the frequency based on the relationship, and a controller controlling velocity of the vibration motor based on the frequency of the first and second frequency signals and the phase difference determined by the phase difference determiner based on the frequency. The relationship between the frequency and phase difference in the phase difference determiner does not include a relationship between frequency lower than a resonance frequency in frequency-velocity characteristics of the vibration motor, and the phase difference.