A general purpose contact algorithm using a compliance contact force model for rigid and flexible bodies of complex geometry

摘要

The analysis of multi-flexible-body dynamics (MFBD) has been an important issue in the area of computational dynamics. Also, dynamic analysis of many mechanical systems often involves contacts among rigid and flexible bodies. But, until now, the contact analysis in the multi-flexible-body dynamics has still remains a big, challenging area. In order to simulate the contact phenomena, this study uses a compliant contact force model based on the Hertzian contact theory. When generating the contact force with a compliant contact force model, a penetration depth and a contact reference frame (a contact point and normal and tangent directions) must be determined from the geometrical information of the rigid and flexible body surfaces. For robust and efficient general purpose contact algorithms, the contact algorithms are divided into four main parts which are a surface representation, a pre-search, and a detailed search and a contact force generation. In the surface representation part, we propose a general surface representation method which can be used for complex rigid and flexible bodies. In the pre-search, the algorithm performs collision detection and composes the input data sets for the detailed search. Then, in the detailed search, the penetration depth and contact reference frame are calculated in order to generate the contact force by using the compliant contact force model. Finally, in the contact force generation part, we evaluate the contact force and the Jacobian matrix which can be used for the implicit integrator. The new general purpose contact algorithm is called GCEOM (General GEOMetry) contact, because it can use general rigid and flexible geometries.