2917 Systematic Analyses of Forward Dynamics of Spatial Closed-loop Mechanisms

Abstract

This paper describes a new method to systematically calculate forward dynamics of spatial closed-loop link mechanisms. Analytical equations to obtain the coefficients of translational and angular accelerations of a moving pair on a crank, two adjacent links with C-S-P pairs, and a coupler link are derived. After solving a system of linear equations with respect to crank accelerations and joint forces and moments, nonlinear differential equations on the mechanism could be solved with a numerical method such as Runge-Kutta method. The calculation program can be easily coded by using some subprogram modules. For an example, forward dynamics of an RSCP spatial 4-bar link mechanism was analyzed in the case where the mechanism started to rotate and the reach to uniform speed of the crank, it was then confirmed that the proposed method was effective and useful.