This paper reviews recent developments of micro ultrasonic rotary motors using piezoelectric resonant vibrations. Following the historical background, four ultrasonic motors recently developed at Penn State University are introduced; windmill, PZT tube, metal tube, and shear-type motors. Driving principles and motor characteristics are described in comparison with the conventional ultrasonic mo...

using piezoelectric patches the stress concentration around a hole on a plate under tension is reduced and controlled. to attain the reduction in stress two placements for piezoelectric patches is investigated. the first location is top/bottom of the hole with compression induced strain and the second is left/right of the hole with tension induced strains to control the stress flow. the result ...

the output of a piezoelectric nanogenerator based on zno nanowire is largely affected by the shape of nanowire. in order to obtain mechanically stable nanogenerator with high performance, the investigation of mechanical and electrical characteristics related to the nanowires and materials used in nanogenerators are of great interest and significance. this paper presents the various behavior of ...

The friction and load variation are the main uncertainties in the linear piezoelectric motor system. Only the viscous friction is considered in previous work, but it is quite different with the practical condition. Highly nonlinear friction in the system is measured and compensated by a radial basis function (RBF) network. A discrete-time sliding mode controller, which is insensitive to the per...

Piezoelectric ultrasonic motors are superior to electromagnetic micro motors, because their efficiency remains theoretically constant during miniaturization. However, the still relatively recent technology has a considerable unexploited optimization potential. Numerical structural analysis by the means of the finite element method (FEM) is a common approach for dimensioning piezoelectric motors...

Piezoelectric nanogenerators (PNGs) are capable of converting energy from various mechanical sources into electric energy and have many attractive features such as continuous operation, replenishment and low cost. However, many researchers still have studied novel material synthesis and interfacial controls to improve the power production from PNGs. In this study, we report the energy conversio...

The development process and experimental investigation of the multicell piezoelectric motor is presented in this paper. proposed design consists three individual cells integrated into stator, double rotor, a preload system. Those elements are combined symmetrical structure motor. two new prototypes have been designed, simulated tested. Finite element numerical analysis carried out to obtain opt...

Piezoelectric polymers have been widely used in a variety of applications, including tactile sensors, energy harvesting, polymer actuators, and biological devices. In this investigation, we fabricated the PLLA (poly(L-lactic Acid)-based bimorph structures for piezoelectric motor applications. First, strain measurement setup was established to measure PDLA film at different temperatures. The eff...

The ineluctable change to micro and subsequently nano has engendered the need for precision control and actuation. With Piezoelectric technology at the heart, a new type of motor is improving small-scale motion systems in a big way. In the following study a novel design of a travelling-wave-type motor based on flexural excitations (d-15 effect) is analyzed using finite element method. The objec...

Traveling Wave Ultrasonic Motor (TWUM) is a compact, precise, and silent actuator generating high torque at low speed without gears. Moreover, the TWUM has a high holding torque without supply, which makes this motor as an attractive solution for holding position of robotic arms. However, their nonlinear dynamics, and the presence of load-dependent dead zones often limit their use. Those issues...