S. M. Afonin’s research while affiliated with National Research University of Electronic Technology and other places

Hysteresis characteristics of a piezotransducer for nano- and micrometric movements are studied; experimental and theoretical hysteresis characteristics with main and partial loops are presented. Transfer function of the nonlinear part with the hysteresis characteristic in the form of the main hysteresis loop for piezotransducer deformation is obtained. The coefficients of harmonic linearization of the hysteresis characteristic of the piezotransducer are determined.

Static and dynamic characteristics of a piezomotor of nano-and micrometric movements for nanotechnology and microelectronics equipment are calculated, the parametric structural diagram of the piezomotor is constructed, and the influence of physical and geometric parameters of the piezomotor on the static and dynamic characteristics is determined.

A study was conducted to prepare a structural parametric model of a pie piezoelectric nanodisplacement transducer. The structural parametric model was prepared to investigate the potential application of the piezoelectric transducer in the equipment of nanotechnology, microbiology, microelectronics, astronomy, for high-precision superposition, compensation, and wavefront correction. It was found that the piezoelectric transducer operates on the basis of the inverse piezoelectric effect, in which a displacement is due to the deformation of the piezoelectric element, caused by the application of an external electric voltage. The wave equations also needed to solved, to construct a structural parametric model of the voltage-controlled piezoelectric transducer.

Absolute stability conditions for the control system of deformation of an electromagnetoelastic converter for nano- and micrometric movements under deterministic and random impacts are obtained.

On the basis of solution of the wave equation and taking into account deformations over coordinate axes, the multidimensional structural-parametric model and the parametric structural diagram of the electromagnetoelastic converter in the form of a piezodrive of nanomotions are constructed. The influence of geometric and physical parameters of the piezodrive and the external load on its static and dynamical characteristics and transfer functions is determined. The parametric structural diagrams of multicoordinate piezo converters are obtained.

The characteristics of the compound pawl and the compound central piezo converter of the step piezodrive are considered. The influence of the geometric and physical parameters of the compound piezo converter and the external load on its static and dynamical characteristics is determined. The transfer functions of the piezo converter as an electromechanical system with distributed or lumped parameters are obtained. The static and dynamical characteristics of the step piezodrive are studied.

The stability conditions for a system controlling the deformation of an electromagnetoelastic transducer under deterministic and random actions are discussed. Manufacturing high-precision electromechanical drives based on electromagnetoelasticity are offering challenges under the scope of nanotechnology, nanobiology, power engineering, microelectronics, and adaptive optics. High precision drives are operated within operating loads ensuring elastic strains of the executive electromagnetoelastic transducer. A system designed for the control of micro and nanoscale strains of an electromagnetoelastic transducer. The absolute stability conditions for a system with hysteresis nonlinearity are analytically described by using Yakubovic's absolute stability criterion. The absolute stability conditions obtained for a system can be used for stability estimation and the calculation of the characteristics of the control system.

The use of the solution to the wave equation to construct a generalized structural parametric model of an electromagnetoelastic transducer to determine the effect of its geometry and physical parameters is discussed. High-precision electromechanical drives are operated under working loads ensuring elastic strains of the executive device. Piezoelectric transducers are characterized by high piezoelectric moduli and they are frequently used to produce nanoscale displacements. The solution of the wave equation supplemented with the corresponding electromagnetoelasticity equation and boundary conditions on the transducer's two working surfaces allows to construct a structural parametric model of an electromagnetoelastic transducer. The transfer functions of a piezoelectric transducer are derived from its generalized structural parametric model and are obtained as the ratio of the Laplace transform of the transducer face displacement to the Laplace transform of the input electric parameter.

For a piezotransducer with a hysteresis characteristic, it is shown that the set of equilibrium positions of its deformation control system is a rest segment and self-oscillations may occur when the piezotransducer end moves. The set of equilibrium positions is determined. An analytical expression is obtained for generalized conditions of absolute stability of a piezotransducer deformation control system.