An Improved Parallel Partitioned Time Integration Scheme based on the Generalized-alpha method for Hybrid Simulation

Hybrid Simulation with Dynamic Substructuring (HSDS) defines a class of hybrid numerical-experimental techniques capable of simulating the nonlinear response of a dynamic system. As far as complexity of emulated structures grows, the role of integration algorithms becomes more and more crucial. In fact, today control systems run at sampling times of the order of 1 ms. Therefore, new displacement commands must be provided at the same rate to generate smooth actuator trajectories. On the other hand, standard computers need more time to solve refined NSs and to integrate the equation of motion. Parallel partitioned time integration algorithms, which allow for the concurrent solution of involved subdomains with different time steps, are recognized as a very effective synchronization strategy. With the objective in mind to overcome major limitations of state-of-art algorithms, an improved parallel partitioned time integration scheme was tailored to first order systems. In detail, a variant of the Generalized-α method was selected as basic monolithic time integrator, for its favorable user controlled algorithmic damping feature. Accuracy, stability and spectral characteristics of the resulting algorithm were derived from numerical simulations of benchmark split-mass systems. Therefore, a Simulink implementation of the proposed method was devised for the xPC-Target real-time operating system for the purpose of its experimental validation. Particular care was devoted to parallelization aspects. Tests conducted on a 4-DoFs split-mass system corroborated the favourable characteristics of the proposed method from the HSDS perspective.JRC.E.4-Safety and Security of Building