Dynamic Models in Multi-Body Systems

Over the last decades, time simulation of mechanisms is performed using special computer programs that implement general formulations, known in the literature as Multi-Body Systems (MBS) formulations. The name is related to the model structure used for the mechanism, which is often regarded as a collection of bodies inter-connected through joints. This paper aims to present an overview of the multi-body formulations as well as a new formulation based on a model in which the mechanism is regarded as a collection of particles rather than bodies. A comparative study is provided, in which the mechanism mobility calculation and interpretation is presented in each case as well as a simulation case study for which the main formulations have been tested. Advantages and disadvantages are discussed for the formulations utilized.