Preface

Jan Awrejcewicz, Marco Amabili, Airton Nabarrete
2021 Meccanica (Milano. Print)  
The present Special Issue follows the 15th conference "Dynamical Systems -Theory and Applications" (DSTA) held in Łódź, Poland, December 2-5, 2019. This international event is organized by the Department of Automation, Biomechanics and Mechatronics (Lodz University of Technology) every two years since 1992. A special group of works of the most interesting topics presented during the DSTA conference and related to modelling and analysis of mechanical systems dynamics were selected. Their authors
more » ... were invited to prepare the extended versions of their papers for publication in this Special Issue. The works underwent a rigorous reviewing process before publication. They fall in the scope of the following topics: bifurcation and chaos in mechanical systems; asymptotic methods in nonlinear dynamics of mechanical systems; modelling and dynamics in life science and bioengineering; original numerical methods of vibration analysis; stability of mechanical systems; nonsmooth mathematical models of mechanical systems and mechatronics. Al-Shudeifat and Saeed aim to further improve the single-sided vibro-impact (SSVI) nonlinear energy sinks (NES), including the coefficient of restitution in the performance optimization. Accordingly, a significant improvement in the performance of the SSVI NES is obtained for specific coefficients of restitution. In addition, a performance comparison is performed between the enhanced SSVIe NES and several existing types of NESs. Awrejcewicz et al. deal with the dynamics of a lumped mass mechanical system containing two nonlinear springs connected in series. The external harmonic excitation, linear and nonlinear damping are included into considerations. The steady and nonsteady resonant vibrations are analyzed by employing the modulation equations of the amplitudes and phases which are yielded by the multiple scales method. Burlon et al. investigate viscoelastic constitutive models involving variable-order fractional operators. A novel formulation of fractional model is proposed to effectively compute the strain response of a viscoelastic material with time-dependent mechanical properties due to any stress input. The main achievement of the paper is proof that the proposed formulation is strictly related to the meaningful fractional model existing in the literature to which, therefore, a reliable mechanical meaning can be given. Cekus et al. present in their paper the analysis of the load motion during the interaction of wind pressure. The mathematical model of load motion is presented, which may be an universal approach for transporting machines equipped with a rope-lifting system. The numerical results are compared with the experiments obtained in the wind tunnel.
doi:10.1007/s11012-021-01321-7 fatcat:xrlmmjy2e5hjfndqrddgfktt3q