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Fuzzy-entropy based robust optimization criteria for tuned mass dampers

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Earthquake Engineering and Engineering Vibration 2010年第2期9卷 285-294页

作者： giuseppe Carlo Marano giuseppe Quaranta Sara Sgobba Department of Environmental Engineering and Sustainable Development Technical University of Bari Department of Structural Engineering and Geotechnics University of Rome "La Sapienza" Faculty of Engineering International University UNINETTUNO

Tuned mass dampers (TMD) are well known as one of the most widely adopted devices in vibration control passive strategies. In the past few decades,many methods have been developed to find the optimal parameters of a TMD installed on a structure and subjected to a random base excitation process,but most of them are usually based on an implicit assumption that all of the structural parameters are deterministic. However,in many real cases this simplification is unacceptable,so robust optimal design criteria becomes aviable alternative to better support engineers in the design process. In Robust Design Optimization (RDO) approaches,indeed the solution must be able to not only minimize the performance but also to limitits variation induced by uncertainty. Most of the currently available RDO methods are based on a probabilistic description of the model uncertainty,even if in many cases they are not able to explicitly include the influence of all the possible sources of uncertainties. Therefore,in this study,a fuzzy version of the robust TMD design optimization problem is proposed. The consistency of the fuzzy approach is studied with respect to the available non-probabilistic formulations reported in the literature and an application to an example of a robust design of a linear TMD subjected to base random vibrations in the presence of fuzzy uncertainties. The results show that the proposed fuzzy-based approach is able to give a set of optimal solutions both in terms of structural efficiency and sensitivity to mechanical and environmental uncertainties.

关键词： tuned mass damper random vibration robust design fuzzy variable expected value fuzzy entropy

Novel four-wing and eight-wing attractors using coupled chaotic Lorenz systems

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Chinese Physics B 2008年第9期17卷 3247-3251页

作者： giuseppe Grassi Dipartimento di Ingegneria dell’Innovazione Università del Salento

This paper presents the problem of generating four-wing （eight-wing） chaotic attractors. The adopted method consists in suitably coupling two （three） identical Lorenz systems. In analogy with the original Lorenz system, where the two wings of the butterfly attractor are located around the two equilibria with the unstable pair of complex-conjugate eigenvalues, this paper shows that the four wings （eight wings） of these novel attractors axe located around the four （eight） equilibria with two （three） pairs of unstable complex-conjugate eigenvalues.

关键词： chaotic attractors multi-wing attractor coupled Lorenz systems dynamical behaviours

Reliability based multiobjective optimization for design of structures subject to random vibrations

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第1期9卷 15-25页

作者： giuseppe Carlo MARANO Department of Environmental Engineering and Sustainable Development Technical University of Bari viale del Turismo 10-74100 Taranto Italy

Based on a multiobjective approach whose objective function (OF) vector collects stochastic reliability performance and structural cost indices, a structural optimization criterion for mechanical systems subject to random vibrations is presented for supporting engineer’s design. This criterion differs from the most commonly used conventional optimum design criterion for random vibrating structure, which is based on minimizing displacement or acceleration variance of main structure responses, without considering explicitly required performances against failure. The proposed criterion can properly take into account the design-reliability required performances, and it becomes a more efficient support for structural engineering decision making. The multiobjective optimum (MOO) design of a tuned mass damper (TMD) has been developed in a typical seismic design problem, to control structural vibration induced on a multi-storey building structure excited by nonstationary base acceleration random process. A numerical example for a three-storey building is developed and a sensitivity analysis is carried out. The results are shown in a useful manner for TMD design decision support.

关键词： Structural optimization Multiobjective optimization (MOO) Random vibration Tuned mass damper (TMD)

Fractional-order systems without equilibria:The first example of hyperchaos and its application to synchronization

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Chinese Physics B 2015年第8期24卷 224-232页

作者： Donato Cafagna giuseppe Grassi Dipartimento Ingegneria Innovazione Università del Salento

A challenging topic in nonlinear dynamics concerns the study of fractional-order systems without equilibrium *** particular, no paper has been published to date regarding the presence of hyperchaos in these systems. This paper aims to bridge the gap by introducing a new example of fractional-order hyperchaotic system without equilibrium points. The conducted analysis shows that hyperchaos exists in the proposed system when its order is as low as 3.84. Moreover, an interesting application of hyperchaotic synchronization to the considered fractional-order system is provided.

关键词： fractional-order systems equilibrium points hyperchaotic systems synchronization

Experimental Characterization of Operation of a Waist-Trunk System with Parallel Manipulators

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Chinese Journal of Mechanical Engineering 2011年第5期24卷 713-722页

作者： CECCARELLI Marco CARBONE giuseppe Laboratory of Robotics and Mechatronics (LARM) University of Cassino

An extensive research activity has been focused on the upper and lower limbs of humanoid robots. However, due to mechanical design difficulties and complex control of multi-body system, the torso of humanoid robot is somehow a neglected or simplified design part. In this paper, operation performance of a new waist-trunk system as torso for humanoid robots is presented through results of lab experimental tests. The proposed waist-trunk system is composed of two 3 DOFs （degrees of freedom） parallel manipulators, which are connected in a serial chain architecture. A prototype is built by using two prototypes of CaPaMan （Cassino Parallel Manipulator）, which are convenient stiff architectures with easy-operation characteristics. Experimental tests are carried out with the aims to imitate lateral-bending and transverse-rotation movements of human torso. Operation performances like displacements, accelerations, and actuation torque are measured for a performance evaluation and design characterization of the used manipulator solution imitating human torso. Experimental test results are illustrated and discussed to show the practical operation feasibility of the proposed architecture and the operation characteristics of the built prototype.

关键词： humanoid robots waist-trunk system parallel manipulators experimental robotics

Novel engineered proteins for mechanomaterials

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Frontiers of Chemical Science and Engineering 2020年第6期14卷 1122-1123页

作者： giuseppe Portale Zemike Institute for Advanced Materials University of Groningen9747 AGGroningenthe Netherlands

In stark contrast to traditional polymer fibers such as nylon and Kevlar,biomaterials[1],e.g.,spider silks and silkworms,exhibit extraordinary mechanical behaviors due to the combination of high strength and high toug... 详细信息

关键词： nylon fibers toughness

Continuous-time chaotic systems: Arbitrary full-state hybrid projective synchronization via a scalar signal

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Chinese Physics B 2013年第8期22卷 333-338页

作者： giuseppe Grassi Dipartimento Ingegneria Innovazione Universitàdel Salento-73100 LecceItaly

Relerrlng to contlnuous-Ume claaotlc systems, tills paper presents a new projective syncnromzatlon scheme, wnlcn enables each drive system state to be synchronized with a linear combination of response system states for any arbitrary scaling matrix. The proposed method, based on a structural condition related to the uncontrollable eigenvalues of the error system, can be applied to a wide class of continuous-time chaotic （hyperchaotic） systems and represents a general framework that includes any type of synchronization defined to date. An example involving a hyperchaotic oscillator is reported, with the aim of showing how a response system attractor is arbitrarily shaped using a scalar synchronizing signal only. Finally, it is shown that the recently introduced dislocated synchronization can be readily achieved using the conceived scheme.

关键词： continuous-time chaotic systems chaos synchronization observer-based synchronization scalarsynchronizing signal

Mechatronic Design of a Robot for Upper Limb Rehabilitation at Home

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Journal of Bionic Engineering 2021年第4期18卷 857-871页

作者： Elio Matteo Curcio giuseppe Carbone Department of Mechanical Energyand Management EngineeringUniversity of Calabria Via BucciCubo 46C87036 RendeItaly

This paper addresses the design of a novel bionic robotic device for upper limb rehabilitation tasks at *** main goal of the design process has been to obtain a rehabilitation device,which can be easily portable and can be managed remotely by a professional *** allows to treat people also in regions that are not easily reachable with a significant cost *** potential benefits can be envisaged,for instance,in the possibility to keep social distancing while allowing rehabilitation treatments even during a pandemic *** attention has been devoted to design the main mechatronic components by developing specific kinematics and dynamics *** design process includes the implementation of a specific control hardware and *** experimental tests are reported to show the effectiveness and feasibility of the proposed design solution.

关键词： bionic robot design simulations parallel robots upper limb rehabilitation

Probabilistic seismic response and reliability assessment of isolated bridges

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Earthquake Engineering and Engineering Vibration 2005年第1期4卷 95-106页

作者： giuseppe Carlo Marano Department of Environmental Engineering and Sustainable Development Technical University of BariTarantoItalyAssistantProfessor

Bridge seismic isolation strategy is based on the reduction of shear forcestransmitted from the superstructure to the piers by two means: shifting natural period andearthquake input energy reduction by dissipation concentrated in protection devices. In this paper,a stochastic analysis of a simple isolated bridge model for different bridge and device parametersis conducted to assess the efficiency of this seismic protection strategy. To achieve this aim, asimple nonlinear softening constitutive law is adopted to model a wide range of isolation devices,characterized by only three essential mechanical parameters. As a consequence of the random natureof seismic motion, a probabilistic analysis is carried out and the time modulated Kanai-Tajimistochastic process is adopted to represent the seismic action. The response covariance in the statespace is obtained by solving the Lyapunov equation for a stochastic linearized system. After asensitivity analysis, the failure probability referred to extreme displacement and the mean value ofdissipated energy are assessed by using the introduced stochastic indices of seismic bridgeprotection efficiency. A parametric analysis for protective devices with different mechanicalparameters is developed for a proper selection of parameters of isolation devices under differentsituations.

关键词： bridge seismic isolation stochastic analysis nonlinear softeningconstitutive law reliability assessment