The present work describes a multiscale methodology which has been developed for modeling of impact damage in the laminated composite structures. The methodology employs the High Fidelity Generalized Method of Cells (HFGMC) micromechanical model for the prediction of the local stress and strain fields, within the representative unit cell of the unidirectional composite material. The Mixed Mode ...

General thermo-mechanical behavior of composites reinforced by shape memory alloy fibers is predicted using a three-dimensional analytical micromechanical method to consider the effect of fibers activation. Composite due to the micromechanical method can be exposed to general normal and shear mechanical and thermal loading which cause to activate the shape memory alloy fibers within polymeric m...

The present paper deals with a micromechanical model of interface able to couple the damage (micro-crack) evolution, the non-penetration conditions (Signorini equations) and the friction effect (Coulomb’s law). At a typical point of the interface, a Representative Volume Element (RVE) is considered; it is characterized by the presence of two different materials and by a microcrack evolving alon...

A topology optimization problem in micromechanical resonator design is addressed in this paper. The design goal is to control the first several eigenfrequencies of a micromechanical resonator using topology optimization. The design variable is the distribution of mass in a constrained domain which we model via (1) the Simple Isotropic Material with Penalization Model and (2) the Peak Function M...

Biomimetic Sensor Modeling and Simulations for Flight Control of a Micromechanical Flying Insect

A 2 DOF resonant thorax structure has been designed and fabricated for the MFI project. Miniature piezoelectric PZN-PT unimorph actuators were fabricated and used to drive a four-bar transmission mechanism. The current thorax design utilizes two actuated four-bars and a spherical joint to drive a rigid wing. Rotationally compliant flexure joints have been tested with lifetimes over 10 cycles. W...

A micromechanical model for 2-D triaxial braided composites is presented. The tow arrangement in the representative unit cell is modeled by solving the packing problem using analytical optimization, avoiding the need to measure the geometric properties experimentally. These results are used in the development of a closed-form micromechanical model predicting the full 3-D stiffness matrix of the...

This paper presents a low cycle fatigue life curve by simulating a crack in a cover plate welded moment connection. Initiation of ductile fracture in steel is controlled by growth and coalescence of micro-voids. This research used a numerical method using finite element modeling and simulation of ductile crack initiation by a micromechanical model. Therefore, a finite element model of a cover p...

This paper presents a nonlinear analytical model for micromechanical silicon ring resonators with bulk-mode vibrations. A distributed element model has been developed to describe the dynamic behavior of the micromechanical ring resonator. This model shows the nonlinear effects in a silicon ring resonator focusing on the effect of large amplitudes around the resonance frequency, material and ele...