Dynamics of planar mechanisms by a modular approach

Abstract

This  work  deals  with  the  forward  dynamics  of  mechanisms  with  one  Degree  of  Freedom  (DOF).  There  is  presented a chain-based General Purpose (GP) method in which a mechanism is disaggregated into structural Assur  groups.  Kinematic  and  force  analyses  of  Assur  groups  are  individually  solved  to  form  a  library  of  independent modules. This property is used to reduce inertial parameters and external forces in each structural group (module) that forms the mechanism. The reduction is propagated from module to module until the driving link  is  reached,  and  then  the  forward  dynamics  is  solved  analyzing  exclusively  that  link.  The  presented  GP  method has a flexibility which is comparable with respect to the GP joint-based methods. The method is applied to  the  forward  dynamics  of  a  six-bar  (Watt)  mechanism  with  results  that  are  comparable  to  the  commercial  software for Multibody Systems (MBS) dynamics.