Energy-leak monitoring and correction to enhance stability in the co-simulation of mechanical systems

Abstract

Non-iterative co-simulation is an increasingly important technique for the simulation of complex mechanical systems. Adopting co-simulation schemes enables the simultaneous use of computational resources and makes it possible to select the most appropriate modelling techniques and algorithms to describe and solve the dynamics of each system component. However, it inherently requires the coupling of different subsystems at discrete communication times, which may compromise the stability of the overall integration process. One of the negative effects of discrete-time communication is the introduction of artificial energy in the system dynamics, which can render the simulation unstable if it accumulates over time. Excess energy can be dissipated introducing virtual damping elements in the subsystem models. The actual amount of damping must be adjusted as the simulation progresses to ensure that all the artificially generated energy is removed from the system while keeping the dynamics realistic. In this paper, we introduce a monitoring framework to keep track of this excess energy, and put forward a dissipation methodology to eliminate it. The ability of this framework to achieve stable non-iterative co-simulation was tested with several mechanical system examples.