Finite Element Modeling and Vibration Control Simulation of a Slewing Nonlinear Flexible Beam Using Arrays of Sensors and Actuators

摘要

The active control of flexible structures has been an active field of research for several decades, mainly due to the increased use of lightweight and lightly damped materials in flexible structures. In comparison to their rigid counterparts these structures present several advantages, such the high payload/weight ratio for power efficiency and fast maneuvering. However, due to their higher flexibility, they exhibit more pronounced vibrations. A viable solution to this problem is the use of arrays of distributed sensors and actuators, coupled with active control strategies, in order to enhance the stiffness and damping properties of the structure [1,2].In this paper, we introduce a new finite element (FE) technique and simulation design tool for static, dynamic, and control analysis of a highly flexible beam, undergoing nonlinear deformations due to fast slewing. Here, piezoelectric elements, which can be employed as discrete patches of lead zirconium titanate (PZT) or a uniform layer of polyvinylidene (PVDF), are used as actuators [3]. As sensors, Fiber Bragg Grating (FBGs) and accelerometers are considered. FBGs are novel optical sensors that are perfectly suited for distributed sensing of flexible structures, capable of providing hundreds of discrete strain (and temperature) measurements per every channel [4].