André Fenili

Mathematical Modelling of a Rotating Nonlinear Flexible Beam-Like Wing

The mathematical modelling of rotating nonlinear flexible beam-like wing with rectangular cross section is investigated here. The structure is mathematically modeled considering linear curvature and clamped-free boundary conditions. The flexible wing has an angle of attack which is considered constant. Nonlinearities resulting from the coupling between the angular velocity of the rotating axis and the transversal vibration of the beam are considered. A drag force and a lift force acting along the beam length are also included in the mathematical model. The drag force is modelled as a turbulent drag effect. The lift force is modeled as a generalized force, using the strip theory. These forces are velocity dependent nonlinear excitations acting on the bean-like wing.

Nonlinear Vibrations in Elastic Structures: Dynamics and Control

Univ Estadual Paulista UNESP, Inst Geociencias & Ciencias Exatas, BR-13506900 Rio Claro, SP, Brazil

Revisiting the Nonlinear Dynamics Behavior,Control Designs and Insights on Fluid Interactions of a Flexible Slewing Spatial Structures and their Applications to Engineering Science

In this lecture,we presented a state -of -the art of the nonlinear dynamics and vibration controls of a flexible slewing structure systems, excited by an ideal and non-ideal energy source( Non-ideal).

Editorial dynamics and control of aerospace and vertical transportation systems

This Special Issue presents a selection of papers initially presented at the 11th International Conference on Vibration Problems (ICOVP-2013), held from 9 to 12 September 2013 in Lisbon, Portugal. The main topics of this Special Issue are linear and, mainly, nonlinear dynamics, chaos and control of systems and structures and their applications in different field of science and engineering. According to the goal of the Special Issue, the selected contributions are divided into three major parts: “Vibration Problems in Vertical Transportation Systems”, “Nonlinear Dynamics, Chaos and Control of Elastic Structures” and “New Strategies and Challenges for Aerospace and Ocean Structures Dynamics and Control”.

The Rigid-Flexible Two Link Manipulator with Joint Friction and Different Number of Modes for the Flexible Link Discretization

A Rigid-Flexibletwo Link Rotatingmanipulator Likesystem is Mathematically Modeled Usinglagrange’s Equations. Two Different Approaches are Considered for the Flexible Linkdiscretization:(a) only the First Flexuralmode is Considered and (b) Two Flexural Modes are Considered. the Mainidea here is to Investigate the Participation of the Second Flexural Mode in the System Dynamics Forslow and Fast Maneuversin the Presence of Friction Forces. Nonlinearity Arises in this Problem Fromthe Coupling between the Variable Representing the Angular Velocity of the Rotating Axis Connected Tothe Flexible Link and the Variable Representing the Vibration of the Flexible Link. Sufficiently Largeangular Velocities are Considered in Order to the System to Undergo Sufficiently Strongnonlinearbehavior.Coulomb Friction Isconsidered on both Joints.For Position/velocity of both Rotating Axesand Elimination of Vibration in the Flexible Link the Nonlinear Control Technique Named Statedependent Riccati Equation (SDRE) is Applied. Theresults for the Different Mathematicaldescriptions of the System are Compared and Discussed

Remarks on the derivation of the governing equations for the dynamics of a nonlinear beam to a non ideal shaft coupling

We derive nonlinear governing equations without assuming that the beam is inextensible. The derivation couples the equations that govern a weak electric motor, which is used to rotate the base of the beam, to those that govern the motion of the beam. The system is considered non-ideal in the sense that the response of the motor to an applied voltage and the motion of the beam must be obtained interactively. The moment that the motor exerts on the base of the beam cannot be determined without solving for the motion of the beam.

A nonlinear model and force control of a robotic claw

The objective of this work is to obtain and analyze a simple representative mathematical model for a robotic claw. The claw is represented here through the interaction between two simple pendulums and a sub-system composed of two masses connected by a spring and a damper. The main approach is based on obtaining the constrained mathematical model that represents the configuration of the system including impact and contact dynamics. The governing equations of motion are obtained using the Euler-Lagrange formalism. The numerical integration of the governing equations is realized using the fourth order Runge-Kutta. The explicit force control technique is used in order to maintain the contact force constant during the contact.