Authors: V. Mkrttchian
Affilation: State Engineering University of Armenia, Armenia
Pages: 497 - 500
Keywords: micro electromechanical systems (MEMS), indicator of sliding mode, observer, anticipatory compensation, discontinuous Control and Setting Adjustment (DC&SA)
Before elaboration and designing of micro electromechanical systems (MEMS) it is very important to carry out an appropriate computer modeling for analyzing and optimizing. To describe adequately the physical phenomenon talking place in MEMS it is necessary to revise the emitting methods of theoretical investigation and choose a suitable one. For theoretical investigation of uniform MEMS several methods have been developed. One of the widely used methods is the well-known coupled-wave theory. For periodical structures transfer matrix method and Bloch wave analysis have been used successfully. Other less employed methods have been devoted for uniform MEMS analysis. They are the Roundís method, a discrete ñ time approach based on a digital signal processing formulation and a Hamiltonian formulation for coupled-wave equations. For nonuniform MEMS transitive and reflective properties investigation the extension of the methods described above has been used. They are the extensions of transfer matrix method, Bloch wave analysis generalization , coupled-wave theory and analysis methods extension. A variation technique and a Hamiltonian approach for non uniform MEMS analysis have been employed also. The all generalized methods for non uniform MEMS investigation have a restriction on the amplitude of modulation. The reason is that for these methods itís significant that the wave equation solution is searched as a superposition of counter-propagating waves. The last condition badly complicates the problem solving in the case of non periodically and strongly modulated media. The proposed non-traditional method of theoretical investigation is free from the above-mentioned drawbacks. It is based on the fact, that a solution of the wave equation in a modulated media is searched in the form of a single expression, but not in the form of generally accepted counter-propagating waves. Such a form of wave equation solution has been proposed by a number of authors and further has been extended, basically, to investigate different types of multilayer structures. This method allows to solve the correct boundary problem not only for linear but for nonlinear media as well. Furthermore, this approach permits to carry out the investigation for media with losses (or gain) and doesn't need any preliminary assumptions concerning the form of wave equation solution (i.e. the form of traveling waves, counter-propagating waves, exponentially increasing or decreasing waves or others in the case of non linearity). with arbitrary modulated media (including nonlinear) and permits to solve numerically diverse problems easily and comparatively rapidly by using of a well-known Runge-Kutta method of numerical integration. For computer modeling of desired type of MEMS the non-traditional method of theoretical investigation issuggested. Preliminary computer co-simulations and optimizations for uniform MEMS (taking into account losses and gain) have been carried out by using of the above-described non-traditional method of theoretical investigation.