A MEMS device includes a semiconductor body with a cavity and forming an anchor portion, a tiltable structure elastically suspended over the cavity, first and second support arms to support the tiltable structure, and first and second piezoelectric actuation structures biasable to deform mechanically, generating a rotation of the tiltable structure around a rotation axis. The piezoelectric actuation structures carry first and second piezoelectric displacement sensors. When the tiltable structure rotates around the rotation axis, the displacement sensors are subject to respective mechanical deformations and generate respective sensing signals in phase opposition to each other, indicative of the rotation of the tiltable structure. The sensing signals are configured to be acquired in a differential manner.

The present disclosure relates to a piezoelectric stick-slip-motor and control method. An exemplary method to enable speed variation of the piezoelectric stick-slip-motor with a reduced noise generation, includes: applying a cyclic sawtooth-waveform drive voltage signal with a constant frequency in which the drive voltage (V) increases to and decreases from a peak voltage (Vp) for operating the motor with a constant speed; and changing the motor speed by gradually increasing or decreasing the gradient (dV/dt) of increasing the drive voltage (V) to the peak voltage (Vp) with each subsequent sawtooth-waveform drive voltage signal cycle (C) while keeping the frequency of the drive voltage signal constant.

A control apparatus for a vibration actuator configured to relatively move a contact body in contact with a vibrator with respect to the vibrator using vibration occurring on the vibrator includes a control amount output unit including a trained model trained to, if an instruction about a first speed to relatively move the contact body with respect to the vibrator at is issued, output a first control amount to relatively move the contact body with respect to the vibrator.

A control apparatus for a vibration actuator configured to relatively move a contact body in contact with a vibrator with respect to the vibrator using vibration occurring on the vibrator includes a control amount output unit including a trained model trained to, if an instruction about a first speed to relatively move the contact body with respect to the vibrator at is issued, output a first control amount to relatively move the contact body with respect to the vibrator.

A piezoelectric drive unit is configured for driving a passive element relative to an active element, wherein the active element includes a resonator with two arms, each extending in parallel to a reference plane and ending in a contact element, which is movable by oscillating movements of the arms and thereby drives the passive element. Each of the arms has, at the outer end of the arm, a protrusion extending inward, toward the other arm, and on at least one of the arms, the respective contact element, arranged at the arm's outer end, extends outward, away from the other arm.

A piezoelectric drive unit is configured for driving a passive element relative to an active element, wherein the active element includes a resonator with two arms, each extending in parallel to a reference plane and ending in a contact element, which is movable by oscillating movements of the arms and thereby drives the passive element. Each of the arms has, at the outer end of the arm, a protrusion extending inward, toward the other arm, and on at least one of the arms, the respective contact element, arranged at the arm's outer end, extends outward, away from the other arm.

A method of controlling a piezoelectric driving apparatus including a vibration section that has a piezoelectric element and a transmission section that transmits vibration of the vibration section to a driven body, and, by energization of the piezoelectric element, vibrates the vibration section in a combination of longitudinal vibration and bending vibration to cause the transmission section to perform an elliptical motion and to move the driven body by the elliptical motion, the method of controlling the piezoelectric driving apparatus including switching, according to an external force received by the driven body, a drive algorithm of the piezoelectric driving apparatus between a first drive mode in which a separation amplitude, which is an amplitude of the longitudinal vibration, is changed while a feed amplitude, which is an amplitude of the bending vibration, is constant and a second drive mode in which both the feed amplitude and the separation amplitude are changed.

A controller is capable of reducing time required to stop a control target at a target stop position as a final stop position. The controller drives a vibration element including a piezoelectric element by an AC signal to thereby move a contact body, in contact with the vibration element, relative to the vibration element. The controller controls a pulse duty cycle of a signal converted to the AC signal based on a difference between a target stop position, which is a final stop position of the contact body, and a current position of the contact body, and an actual speed of the contact body.

A controller is capable of reducing time required to stop a control target at a target stop position as a final stop position. The controller drives a vibration element including a piezoelectric element by an AC signal to thereby move a contact body, in contact with the vibration element, relative to the vibration element. The controller controls a pulse duty cycle of a signal converted to the AC signal based on a difference between a target stop position, which is a final stop position of the contact body, and a current position of the contact body, and an actual speed of the contact body.

A control device for a vibration-type actuator includes a control unit including first and second output units. The first output unit includes a first learned model subjected to machine learning in such a way as to output a first control amount for causing the contact body to relatively move with respect to the vibrator. The second output unit includes a second learned model subjected to machine learning in such a way as to output a second control amount, which is data of the same data format as that of the first control amount. The control unit updates parameters of the first learned model and parameters of the second learned model based on a control deviation, which is a difference between the first control amount and the second control amount output within the same sampling period as that of the first control amount.