Title :
Implicit Multibody Penalty-BasedDistributed Contact
Author :
Hongyi Xu ; Yili Zhao ; Barbic, Jernej
Author_Institution :
Dept. of Comput. Sci., Univ. of Southern California, Los Angeles, CA, USA
Abstract :
The penalty method is a simple and popular approach to resolving contact in computer graphics and robotics. Penalty-based contact, however, suffers from stability problems due to the highly variable and unpredictable net stiffness, and this is particularly pronounced in simulations with time-varying distributed geometrically complex contact. We employ semi-implicit integration, exact analytical contact gradients, symbolic Gaussian elimination and a SVD solver to simulate stable penalty-based frictional contact with large, time-varying contact areas, involving many rigid objects and articulated rigid objects in complex conforming contact and self-contact. We also derive implicit proportional-derivative control forces for real-time control of articulated structures with loops. We present challenging contact scenarios such as screwing a hexbolt into a hole, bowls stacked in perfectly conforming configurations, and manipulating many objects using actively controlled articulated mechanisms in real time.
Keywords :
Gaussian processes; PI control; computer animation; mechanical contact; real-time systems; singular value decomposition; SVD solver; articulated rigid objects; articulated structures; complex conforming contact; computer animation; computer graphics; exact analytical contact gradients; implicit multibody penalty; implicit proportional-derivative control forces; real-time control; self-contact; semiimplicit integration; stability problems; stable penalty-based frictional contact; symbolic Gaussian elimination; time-varying contact areas; time-varying distributed geometrically complex contact; Computational modeling; Dynamics; Equations; Force; Friction; Mathematical model; Torque; Computer graphics; animation; kinematics and dynamics; physically based modeling;
Journal_Title :
Visualization and Computer Graphics, IEEE Transactions on
DOI :
10.1109/TVCG.2014.2312013