This paper presents solution of kinematics analysis of a specific class of serial-parallel manipulators, known as 2-(6UPS) manipulators, which are composed of several modules consisting of elementary manipulators with the parallel structure of the Stewart platform, by artificial neural network. At first, the kinematics model of the hybrid manipulator is obtained. Then, as the inverse kinematics problem of this kind of manipulators is a very difficult problem to solve because of their highly nonlinear relations between joint variables and position and orientation of the end effectors, a wavelet based neural network (wave-net) with its inherent learning ability as a strong method was used to solve the inverse kinematics problem. Also, the proposed wavelet neural network (WNN) is applied to approximate the paths of middle and upper plate in a circular and a spiral path, respectively. The results show high accurate performance of the proposed WNN.
In this paper, for a class of the complex nonlinear system control problems, based on the two-person zero-sum game theory, combined with the idea of approximate dynamic programming(ADP), the constrained optimization control problem is solved for the nonlinear systems with unknown system functions and unknown time-varying disturbances. In order to obtain the approximate optimal solution of the zero-sum game, the multilayer neural network is used to fit the evaluation network, the execution network and the disturbance network of ADP respectively. The Lyapunov stability theory is used to prove the uniform convergence, and the system control output converges to the neighborhood of the target reference value. Finally, the simulation example verifies the effectiveness of the algorithm.
In this paper, a modified version of the Chaos Shift Keying (CSK) scheme for secure encryption and decryption of data will be discussed. The classical CSK method determines the correct value of binary signal through checking which initially unsynchronized system is getting synchronized. On the contrary, the new anti-synchronization CSK (ACSK) scheme determines the wrong value of binary signal through checking which already synchronized system is loosing synchronization. The ACSK scheme is implemented and tested using the so-called \emph{generalized Lorenz system} (GLS) family making advantage of its special parametrization. Such an implementation relies on the parameter dependent synchronization of several identical copies of the GLS obtained through the observer-based design for nonlinear systems. The purpose of this paper is to study and compare two different methods for the anti-synchronization detection, including further underlying theoretical study of the GLS. Resulting encryption schemes are also compared and analyzed with respect to both the encryption redundancy and the encryption security. Numerical experiments illustrate the results.
The methodology of modelling and of qualitative analysis of large rotating systems with gear and bearing couplings is presented. The emphasis is laid on the modelling of nonlinear gear and bearing couplings and on their influence on the dynamic system response to the internal kinematic excitation in gearing and to parametric excitation caused by the time-varying meshing stiffness. The aim is to introduce a method of investigation the beahviour of the rotating system influenced by the mentioned excitation and to examine the influence of chosen operational parameters. The methodology of modelling and of qualitative dynamic behaviour analysis is tested on a two-stage gearbox. and Obsahuje seznam literatury
In this paper differential forms and differential algebra are applied to give a new definition of realization for multivariable nonlinear systems consistent with the linear realization theory. Criteria for the existence of realization and the definition of minimal realization are presented. The relations of minimal realization and accessibility and finally the computation of realizations are also discussed in this paper.
A mathematical model of the roadway automobile motion is numerically analyzed. This model is intended to describe the roadway automobile stability. A previous paper [6] described the model in detail and the general method of qualitative analysis. In the present paper, we continue the discussion of stability by numerical simulations and the specific question we attempted to answer is: which parameter(s) of automobile geometry and quality of the roadway can serve as a reliable predictors) for car crash? Data from Daimler-Chrysler AG and Ford Motor Company Limited were used for that purpose, considering three car types - Mercedes-Benz E 320 (T-modelle), Ford Focus and Mercedes-Benz Sprinter (1). Hence, one can consider the present work as a natural continuation of [6]., Obsahuje seznam literatury, and Článek doplňuje Appendix na str. 294-295