Ultrasonic Piezomotors

The operation generally involves two distinct phases: the excitation of a stator and the frictional coupling with a rotor. When an alternating current is applied to the piezoelectric element at a resonant frequency—usually in the ultrasonic range (20 kHz to several MHz)—the stator begins to vibrate. However, the motor does not rely on a simple back-and-forth vibration. Instead, specific geometries and electrode patterns are used to induce a "traveling wave" or an elliptical motion at the contact point of the stator.

. Unlike traditional magnetic motors, they use the inverse piezoelectric effect to create microscopic, resonant oscillations in a ceramic element, which are then converted into linear or rotary motion through frictional contact. BDML Stanford +2 Core Operating Principles The motion of an ultrasonic motor is based on the interaction between a vibrating stator and a moving part (rotor or runner). Based on research from Physik Instrumente (PI) , these are the primary methods: Standing-Wave Motors: These operate on a "micro-impulse" principle. The piezo element is excited at a resonant frequency that creates a stationary vibration pattern. This vibration pushes against the runner at an angle, moving it forward in a series of tiny, high-frequency steps. Traveling-Wave Motors: A traveling wave is generated along the surface of the stator (often a ring or disk). Points on the surface move in an elliptical path, "carrying" the rotor along as the wave propagates. Hybrid-Mode Motors: These combine different vibration modes (such as longitudinal and bending) to achieve specific performance characteristics, such as higher torque or bidirectional control. BDML Stanford +4 Key Advantages Experts at PI-USA and Tekceleo highlight several distinct benefits over conventional electromagnetic motors: 11 sites (PDF) The Ultrasonic Piezo Drive An Innovative Solution for High- ... The paper introduces a new concept of a versatile piezo motor driven at ultrasonic frequency, and it elaborates on a number of spa... ResearchGate Actuator 2006: Ultrasonic Piezo Motor: Survey of the Various ... Ultrasonic Piezomotors. An ultrasonic piezomotor is one in which electrical energy is converted by the inverse piezo-effect to obt... BDML Stanford PILine® Ultrasonic Piezomotors - PI France Applications. PILine® ultrasonic piezomotors are small, high-speed and cost-efficient. Ideally suita- ble for applications of low ... PI France Show all Self-Locking at Rest: Because the motor relies on friction between the actuator and the runner, it remains in position even when powered down without requiring additional brakes. High Precision & Speed: They can achieve nanometer-scale resolution while maintaining high velocities (up to 500 mm/s or more) and fast "step-and-settle" times. Non-Magnetic & Vacuum Compatible: Since they do not use coils or magnets, they are ideal for MRI environments, electron microscopy, and aerospace applications. Silent Operation: Because the driving frequency is in the ultrasonic range, the motor is virtually inaudible to humans . Common Applications Optics and Imaging: Precision focusing in camera lenses and ultrasonic piezomotors

Ultrasonic piezomotors offer a distinct set of advantages that make them superior to electromagnetic motors in niche applications. The most significant is their high power-to-weight ratio. Because they do not require copper windings, iron cores, or permanent magnets, they can be significantly lighter and more compact than motors of comparable torque. The operation generally involves two distinct phases: the

Ultrasonic piezomotors are high-precision drive systems that convert electrical energy into mechanical motion through high-frequency vibrations. Unlike traditional electromagnetic motors that use magnets and coils, these devices rely on the to create microscopic oscillations in the ultrasonic range (typically above 20 kHz). Core Operating Principles Instead, specific geometries and electrode patterns are used