MODELING ISSUES FOR REAL-TIME PERFORMANCE IN FLEXIBLE MULTIBODY SYSTEMS

Abstract. In recent years, our group has worked on real-time methods for the dynamics of flexible and rigid multi-body systems. In order to develop such methods, attention must be paid, in an integrated way, to modeling issues, formulation of the equations of motion, nu-merical integration procedures, and implementation techniques. Achievement of real-time performance in flexible multi-body systems on conventional PC platforms is commonly more challenging than in the rigid case. It can be stated that most methods developed for rigid multi-body systems can be extended to consider flexible members. Consequently, conclusions and recommendations drawn when studying rigid mechanisms in order to achieve real-time performance can be extrapolated to the flexible case. However, some additional “degrees-of-freedom ” arise when simulating the motion of flexible multi-body systems, which must be managed by the analyst. They are the choice, for each of the flexible bodies, of the accuracy level to be applied for the description of the corresponding flexible component. This is some-thing affecting the modeling stage, and occurs no matter the selected modeling technique is. In this paper, the described topic is addressed, in the context of a floating reference frame formulation with modal superposition of static and dynamic modes with fixed boundaries