Modular and distributed forward dynamic simulation of constrained mechanical systems – A comparative study

In this paper, we examine the modular development of two alternate methods for distributed computation of the forward dynamics simulations of constrained mechanical systems. We exploit the natural spatial parallelism of closed-chain linkages, initially, for the modular development of overall dynamics, and subsequently, for the distributed numerical simulation of the dynamics. Traditionally, the numerical simulation problem of constrained mechanical systems has been treated as two separate stages: the problem of algorithm development and the subsequent numerical problem of advancing the discretized differential equations in time. However the potential numerical instabilities arising from the formulation stiffness of the algorithm development stage has the potential to hinder the subsequent numerical integration stage. These aspects are also explored during the evaluation of the two alternative approaches for the distributed forward dynamics simulation of a four-bar linkage. A series of tests were performed on a real-time synchronized distributed computational system (RT-LAB) to evaluate the performance of both methods of simulation and preliminary results to quantify the overall computational efficiency and accuracy are presented.