نوع مقاله : مقاله پژوهشی
نویسندگان
1 دانشجوی دکتری، گروه مکانیک، دانشکده مهندسی، دانشگاه فردوسی مشهد، ایران
2 دانشیار، گروه مکانیک، گروه مکانیک، دانشکده مهندسی، دانشگاه فردوسی مشهد، ایران قطب علمی رایانش نرم و پردازش هوشمند اطلاعات (SCIP)
چکیده
کلیدواژه‌ها
موضوعات
عنوان مقاله [English]
نویسندگان [English]
In this study, dynamic behavior of a micro scale parallelogram flexure under end load conditions is studied. To this end, by making use of the modified strain gradient elasticity along with the beam constraint model, the nonlinear strain energy of a single flexure beam and consequently a parallelogram flexure is derived in terms of its end displacements. Then, using the Lagrange equations, a dynamic model is presented for the parallelogram flexure. To enable the study of small amplitude oscillations around the operating point, the proposed dynamic model is linearized about the static equilibrium sate. Then the allowable regions for application of static axial and transverse forces, so that the utilized nonlinear theory is not violated and at the same time, the system remains stable, is found. Obtained results show that the classical theory underestimates the stability of the parallelogram flexure. Moreover, the natural frequencies and mode shapes of the system was also derived and their dependence to the length scale parameters and the static loading condition is analyzed. It is observed that with reducing the dimensions, or increasing the length scales, the difference between the predictions of the classical theory with that of the modified strain gradient theory is increased. Moreover, it is observed that increasing the transverse load leads to a decrease, while increasing the axial load, leads to an increase in natural frequencies.
کلیدواژه‌ها [English]
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