The present invention relates to a microfluidic pump for generating forced traveling waves that can directly drive liquid. A surface traveling wave-driven microfluidic pump comprises a channel with two opposing channel walls. Two symmetric traveling waves are generated on the surface of two opposite channel walls. The channel contains liquid that becomes trapped inside the cavities and is pumped along the direction of the traveling wave at the same speed as the traveling wave.

A virtual resistive load feedback circuit for driving a piezoelectric actuator is provided that accounts for a hysteresis error and drift within the movement of the actuator. The circuit may include a voltage divider and charge divider. A voltage monitor signal corresponding to a voltage of a driver signal and a current monitor signal corresponding to a current provided to the amplifier are combined by an operational amplifier and include electrical characteristics of the actuator such that the circuit approximates a virtual load across the actuator. A feedback portion of the operational amplifier may include a resistor and capacitor connected in parallel to provide the voltage and charge divide functions. The use of the virtual resistive circuit allows for the piezoelectric actuator to be ground referenced, with no external components connected directly to the actuator while gaining the feedback effect to counter the hysteresis and drifts errors of the actuator.

A vibration actuator that is capable of reducing differences in vibration phase and vibration amplitude without rising a voltage of a drive circuit when driving a contact member using a plurality of vibrators connected in series. A vibration actuator includes a vibrator device and a contact member that moves relative to the vibrator device. The vibrator device includes transformers of which primary coils are connected in series, and vibrators that are respectively connected in parallel to secondary coils of the transformers.

A vibration actuator that is capable of reducing difference of vibration velocities when a contact member is driven using a plurality of vibrators. The vibration actuator includes a vibrator device and a contact member that moves relative to the vibrator device. The vibrator device includes a plurality of vibrators that are connected in series, and a plurality of inductors that are connected in parallel to the respective vibrators.

An electromechanical stator includes an actuator section, a support section and a spring section. A continuous sheet of elastic material constitutes at least a part of each of these sections. The actuator section includes a vibration body and a moved-body interaction portion. The vibration body includes an electromechanical volume. The spring section is elastic, with a spring constant, enabling provision of a normal force in the vibration direction upon displacement of the fixation point. Also an electromechanical motor and a method of operating such an electromechanical motor are disclosed.

A defrosting device includes an actuator including: a stationary portion and a movable portion configured to alternately move away from and move towards the stationary portion, and an intermediate element including a loading portion configured to be pushed by the movable portion of the actuator when the movable portion of the actuator moves away from the stationary portion, and a movement transmission portion configured to move according to the movement of the loading portion and to push a part to be defrosted to deform the part to be defrosted. The movable portion of the actuator and the loading portion of the intermediate element are not connected to one another, such that the loading portion of the intermediate element cannot pull the movable portion of the actuator to move same away from the stationary portion.

A driver for a circuit with a capacitive load is configured for coupling to a voltage source which provides a DC input voltage, and is configured to generate an output voltage at an output. The driver includes a bidirectional synchronous power converter with a first switch, a second switch, and an inductive device connected to the first and/or second switch. A controller is configured to control the first switch and the second switch. The bidirectional synchronous power converter generates a switching voltage from the input voltage at a switching node and generates the output voltage having an analog voltage waveform with a peak amplitude of at least twice the input voltage. The bidirectional synchronous power converter includes a boost-buck converter configured to generate the analog voltage waveform from the input voltage by transferring increments of energy to the capacitive load in a forward-boost mode and from the load in a reverse-buck mode.

The invention relates to an electronic circuit (100) for controlling charging of a piezoelectric load (190). The electronic circuit comprises a charge pump (111) configured to supply a charging current to the piezoelectric load dependent on a charge control signal (131), a measurement circuit (113) configured to obtain a load voltage corresponding to a terminal voltage at a load terminal of the piezoelectric load, a comparator circuit (114) configured to compare an adjustable reference voltage with the load voltage. The electronic circuit is configured to determine the charge control signal dependent on the comparison so that the control signal controls delivery of the charging current dependent on the comparison. The electronic circuit is further configured to set the adjustable reference voltage to a target voltage (VT) and to set the adjustable reference voltage to a low limit voltage (Vlow), being lower than the target voltage, when the load voltage reaches the target voltage.

A single ended n-bit hybrid digital-to-analog converter is configured to receive as an input an analog signal and produce an n-bit digital output. The converter includes a split main sub-digital-to-analog converter capacitor array, a most significant bit capacitor array, and a main capacitor array. A coupling capacitor couples the main array to the split main sub-digital-to-analog convert.

Provided are a piezoelectric driving device, an optical member driving device, a camera device, and an electronic apparatus, which are capable of driving an object to be driven in one direction by oscillation in the one direction, and of driving the object to be driven in two directions by combining the driving in one direction. A piezoelectric driving device (18) includes: a driving portion (38) to be brought into frictional contact with an object to be driven (16), which is moved with respect to a fixed body (12); and at least two piezoelectric portions (40a to 40d), which are formed integrally with the driving portion (38), are arranged on a predetermined plane with the driving portion (38) being sandwiched between the at least two piezoelectric portions (40a to 40d), and are configured to be bent with respect to the predetermined plane when voltages are applied to the at least two piezoelectric portions (40a to 40d), wherein outer edges of entirety of the at least two piezoelectric portions (40a to 40d) are fixed to the fixed body (12).