A method is disclosed for closed-loop motion control of an ultrasonic motor having at least one actuator with an excitation electrode and at least one common electrode, an element to be driven, a controller and at least one electrical generator for generating at least first and second excitation voltages U1 and U2 to be applied to the electrodes of the actuator for vibration of the actuator. A friction element of the actuator, due to its vibration, intermittently contacts the element to be driven with a driving force. The method includes providing the at least two excitation voltages U1 and U2 with different resemblance frequencies, a frequency difference deviating from a servo sampling frequency of the controller by 5 kHz at the most, and simultaneously applying the excitation voltages to the electrodes of the actuator.

A high-precision linear actuator (1) comprises: a first straight-guide mechanism (11A, 11B, 11C), which guides movements of an actuator element (4) and a working device (6) relative to an actuator housing (3); a pressing mechanism (7, 8, 9), which in a pressing-contact condition presses the actuator frame (2) and the actuator housing (3) with a predetermined force against one another; and a second straight-guide mechanism (12A, 12B), which guides movements of the actuator housing relative to the actuator frame between said pressing-contact condition and released-contact conditions in which the pressing mechanism presses the actuator frame and the actuator housing towards one another. The invention provides a safety mechanism which automatically reinstates negative consequences of unforeseen collisions in the working environment. In addition the invention allows for a compact and light-weight design of the actuator element and the working device, which improves operational speed and effectivity of the linear actuator.

An optical driving mechanism is provided, configured to force an optical element, including a base, a movable portion, and a driving portion. The movable portion is disposed and connected to the base. The movable portion includes a holder configured to sustain the optical element, a magnetic element, and a fixing member. The magnetic element and the fixing member are affixed to the holder, wherein the fixing member has a permeable material. The driving portion is configured to force the movable portion to move relative to the base, wherein the driving portion includes a piezoelectric element and a support member connecting thereto. The piezoelectric element and the support member are disposed on the base and connected to the movable portion. The fixing member makes contact with the support member via a magnetic attraction force between the magnetic element and the fixing member.

An ultrasonic linear actuation device includes a mover and a plurality of stator sets. The mover includes at least one mover rack. The plurality of stator sets is located in correspondence with the mover. Each of the plurality of stator sets includes an actuating component and a plurality of stator racks. The actuating component is used for stimulating corresponding one of the plurality of stator sets to generate standing-wave oscillations in an oscillation direction, such that the plurality of stator racks of each of the plurality of stator sets can engage the at least one mover rack of the mover to allow the stator racks to mesh the corresponding mover rack and thus to displace the mover in a moving direction.

A piezoelectric unit includes a piezoelectric element that expands and contracts in a first direction, a drive shaft connected with a first end surface of the piezoelectric element, a weight connected with a second end surface of the piezoelectric element, a protection member covering at least a part of the piezoelectric element, the drive shaft, and the weight, and a movable member engaged with the drive shaft. An inner wall surface of the protection member includes a weight position regulating portion that regulates a position of the weight, an element position regulating portion that regulates a position of the piezoelectric element, and a shaft position regulating portion that regulates a position of the drive shaft. An outer wall surface of the protection member has a movable member regulating portion that prevents the movable member from approaching the piezoelectric element.

Embodiments of the invention include a self-propelled sensor system. In an embodiment, the self-propelled sensor system includes a piezoelectrically actuated motor that is integrated with a substrate. In an embodiment, the self-propelled sensor system may also include a sensor and an integrated circuit electrically coupled to the piezoelectrically actuated motor. Embodiments of the invention may also include self-propelled sensor systems that include plurality of piezoelectrically actuated motors. In an embodiment the piezoelectrically actuated motors may be one or more different types of motors including, but not limited to, stick and slip motors, inchworm stepping motors, standing acoustic wave motors, a plurality of piezoelectrically actuated cantilevers, and a piezoelectrically actuated diaphragm. Additional embodiments of the invention may include a plurality of self-propelled sensor systems that are communicatively coupled to form a sensor mesh.

A cartridge for a high intensity focused ultrasound (HIFU) device and a piezoelectric linear motor are disclosed. By using the cartridge for a HIFU device according to the present invention, a transducer module is coupled to a piezoelectric linear motor driveable in water and embedded in the cartridge, heat generated when a conventional step motor is driven is fundamentally removed, an additional cooling fan is not needed, ultra-low power consumption and ultra-precise transfer can be realized, and thus an effective procedure can be performed. A skin beauty device may include ultrasound and high frequency units, apply a high frequency to a skin to be treated so as to crack a stratum corneum, and apply ultrasound to the skin to be treated, and thus a medicament drug can easily penetrate the treated skin. In addition, the piezoelectric linear motor in which a piezoelectric actuator and a moving shaft are stably coupled is provided.

A control device and a control method for a piezoelectric inertia motor are provided. In the stick phase, a first switching element and a second switching element are switched in directions opposite to one another by pulse width modulation, where a time component of a first switching state of ON and OFF increases relative to a time component of a second switching state of ON and OFF, the pulse width modulation is filtered by the capacitive piezoelectric actuator and an inductance, and a first charging operation is carried out, and the time components of the first switching state and the second switching state are reversed at the beginning of a slip phase, and thereby carrying out a second charging operation in the opposite direction to the first charging operation at the capacitive piezoelectric actuator. By storing electromagnetic energy in the inductance, the configuration provided allows for the reduction of energy dissipation as heat and can contribute to an energy-efficient drive for inertia motors.

An optical driving mechanism is provided, configured to force an optical element, including a base, a movable portion, and a driving portion. The movable portion is disposed and connected to the base. The movable portion includes a holder configured to sustain the optical element, a magnetic element, and a fixing member. The magnetic element and the fixing member are affixed to the holder, wherein the fixing member has a permeable material. The driving portion is configured to force the movable portion to move relative to the base, wherein the driving portion includes a piezoelectric element and a support member connecting thereto. The piezoelectric element and the support member are disposed on the base and connected to the movable portion. The fixing member makes contact with the support member via a magnetic attraction force between the magnetic element and the fixing member.

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.