Forward Dynamics of the Five-Bar Parallel Mechanism in Presence of Singularities

Simulation of motion of dynamic systems is addressing the interest of the robotic and mechatronic communities with the goal to have a full digitalization of the physical system (digital twin). The final goal consists of exchanging data from/to the system and to use the model as predictor and even corrector of the system motion. The first step of the application described is to implement a dynamic model able to simulate the behaviour of the system under several conditions. This paper deals with the solution of the forward dynamics problem of a planar five-bar parallel mechanism in presence of singular configurations. In the paper the index-3 augmented Lagrangian formulation with velocity and acceleration projections is implemented to overcome the kinematic combined and the constraint singularities.