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Piezoelectric motors (usually called ultrasonic) show interesting characteristics. Not only they deliver high torques at low speeds but their structure confers to them a braking torque without energy supply. This paper firstly present a list of possible so ...
In this article a high performance Extended Kalman filter algorithm is used to estimate rotor speed, rotor position and load torque in a Hybrid Stepper Motor (HSM). Together with a PI speed controller, the Kalman filter forms a very robust sensorless close ...
This paper is related to the characteristics of a traveling wave ultrasonic linear motor. After a brief state of the art of this type of motor, the working principle is presented. Then, to describe analytically the phenomena existing, a theoretical model i ...
Lead oxide based ferroelectrics, represented by lead zirconate titanate (Pb(Zr,Ti)O-3) or PZT) are the most widely used materials for piezoelectric actuators, sensors and transducers due to their excellent piezoelectric properties. Considering lead toxicit ...
For the development of high precision mobile microrobots with a size of about one cm3, capable of micromanipulation tasks, small and precise actuators have to be developed in order to provide the microrobot and its manipulation tools with the required degr ...
Energy consumption is a major issue for inertial drives with piezoelectric actuators that are integrated in autonomous devices. This paper discusses some theoretical aspects and some experimental results about the energy consumption of inertial drives with ...
A comparative study on the two different kinds of ultrasonic linear motors (ULM), standing and travelling wave types, is described. Analytical modeling using the wave theory and the contact mechanisms is presented. The former is used to describe the wave p ...
Extended Kalman filtering techniques have been successfully used as sensorless control schemes on many different types of synchronous motors. One big disadvantage of the extended Kalman filtering technique is the large computational cost. Even with today's ...
In many miniature systems for positioning and especially in microrobotics the assembly of the components becomes difficult. At sizes of systems of a few cm2 not only the assembly becomes more difficult, downscaling also means that single parts become more ...
Based on a mathematical model, simulation results show how the mechanical performances of the motor are sensitive to the prestressing force. A test bench has been developed in the laboratory for experimental measurements. The motor is driven by a two-phase ...