Most studies tackling hysteresis identification in the technical literature follow white-box approaches, i.e. they rely on the assumption that measured data obey a specific hysteretic model. Such an assumption may be a hard requirement to handle in real applications, since hysteresis is a highly individualistic nonlinear behaviour. The present paper adopts a black-box approach based on nonlinea...

Smart material actuators like Piezoelectric(PZT) are widely used in Micro/Nano manipulators, but their hysteresis behaviors are complex and difficult to model. Most hysteresis models are based on elementary quasistatic operators and are not suitable for modeling ratedependent or thermal-drift behaviors of the actuators. This work proposes a Preisach model based neurodynamic optimization model t...

This paper describes an algorithm to control a two stage hydraulic servovalve designed for aerospace applications. The valve has a piezoelectric ring bender actuating a first stage spool with a significant amount of overlap to reduce internal leakage. The piezoelectric ring bender is a less complex and lighter alternative to a conventional torque motor. The second stage has electrical instead o...

This paper is concentrated on control system design for an XY parallel micromanipulator with piezoelectric actuation. The decoupled property of the manipulator enables the employment of single-inputsingle-output controllers for the two working axes. To compensate for nonlinear hysteresis effect stemming from piezoelectric actuator, the dynamics with Bouc-Wen hysteresis model is derived and iden...

Magnetorheological (MR) dampers represent one of the most promising semi-active control devices for applications aiming at the seismic risk mitigation of new or existing civil structures. Two 30 kN MR dampers were experimentally tested subjecting them to assigned conventional displacement laws at their ends. The paper describes the main results of the above experimental activity and aims at imp...

The purpose of the present paper is to provide proofs of some of the results announced in the survey paper [13]. These results deal with combinatorial topology, in particular with complexes associated with posets of subgroups of a finite group. For applications to group theory, the reader can refer to the above mentioned paper [13]. In his influential paper [11], Quillen proved that the poset S...

The bulk of spontaneous basal ganglia hemorrhages result from rupture of the small perforating intracerebral arteries and a clinical background of hypertension. Charcot and Bouc hard [1] noted that most microaneurysms occurred in hypertensive brains due to miliary microaneurysms involving branches of lenticu lostriate and thalamoperforating arteries. Such microaneurysms were subsequently demons...