A fast contraction mapping for solving multibody systems

The simulation of complex multibody systems with contacts and friction requires a fast and robust solver for complementarity problems. This work presents an efficient method which can solve large cone‐complementarity problems by means of a fixed point iteration. Our method performs like a contractive mapping, providing a monotonic approximation to the exact solution. The algorithm features high computational performance even if thousands of unilateral constraints are added to the system. Also, this scheme fits well in a real‐time simulation context because it can be terminated prematurely. As a benchmark for testing the method in challenging situations, we propose the simulation of the granular flow in a fourth‐generation bebble‐bed nuclear reactor, including 150'000 rigid bodies and more than a million of constraint multipliers. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)