Evaluation of stress mechanisms
Introduction
Dynamic analysis includes the analysis of the forces, displacements, velocities and accelerations that appear in a structure or mechanism as a result of the displacements and deformations that appear in the structure or mechanism.
Much of these analyzes can be simplified by reducing the mechanism or structure to a linear system, making it possible to apply the principle of superposition to work with simplified cases of the mechanism.
Dynamic analysis of mechanisms
Contenido
El análisis dinámico de mecanismos tiene por objeto determinar el movimiento de un mecanismo, las fuerzas y los esfuerzos internos que aparecen sobre cada uno de sus elementos en cada posición de funcionamiento.
Direct or Newton method
This method analyzes a mechanism considering each of its rigid parts as a perfect rigid solid, and proposes a system of differential equations of motion directly based on Newton's laws, which in general is complex and difficult to integrate since rarely the choice of coordinates and references will respect the useful symmetries of the problem. A trivial variation of this method is to write and introduce angular coordinates, in order to write some of the equations of motion in terms of moments of forces, thus the basic equations used in the direct method are:
d'Alembert method
This method uses d'Alembert's Principle, which is an extension of Newton's second law that takes into account the bonds existing between various elements. Using this method instead of the direct method greatly simplifies the equations.
Dynamic analysis of structures
El análisis dinámico de estructuras se refiere al análisis de las pequeñas oscilaciones o vibraciones que puede sufrir una estructura alrededor de su posición de equilibrio. El análisis dinámico es importante porque ese movimiento oscilatorio produce una modificación de las tensiones y deformaciones existentes, que deben tenerse en cuenta por ejemplo para lograr un diseño sísmico adecuado.