We distinguish between, and discuss the applicability of, two levels of rigidity in rigid-body collision modeling. For rigidity in the strong, force-response, sense collisional contact deformations must be highly localized. The bodies then move according to second order rigid-body mechanics during the collision. Incremental collision laws and most collision models using continuum mechanics for ...

We present a fast method for solving rigid body contact problems with friction, based on optimizations incorporated into Lemke’s algorithm for solving linear complementarity problems. These optimizations improve computation time in general and reduce the expected solution complexity from O(n) to nearly O(nm+m), where n and m are the number of contacts and rigid bodies. For a fixed number of bod...

The vertical and rocking impedances of a rigid foundation resting on a semi-infinite transversely isotropic medium are obtained in the frequency domain. In the present approach, the contact pressure distribution on the soil foundation-interface is approximated by a linear combination of known pressure patterns. It is shown herein that the approximate solutions of spatial displacement distributi...

In this paper, we study the quasi-static motion of an elastically suspended, unilaterally constrained rigid body. The motion of the rigid body is determined, in part, by the position controlled motion of its support base and by the behavior of the elastic suspension that couples the part to the support. The motion is also determined, in part, by contact with a frictional surface that both coupl...

We study a class of problems involving the motion of a linear elastic body in frictional contact with a linear elastic half space. The dynamic effects considered are the inertial properties of the body regarded as rigid. We study only those regimes of contact interaction for which the slip velocity with the body taken as absolutely rigid and the time rate of change of the elastic displacements ...

Contact lens correction of astigmatism is reviewed. According to literature data, rigid gas permeable lenses are the lenses of choice in correction of irregular and high astigmatism. The crucial advantage of rigid gas permeable lenses is clear vision and stable correction of astigmatism. Soft toric lenses ensure quick adaptation and comfort. The most prominent disadvantage of soft toric contact...

We propose a model-based control framework for multi-arm manipulation of a rigid object subject to external disturbances. The control framework, based on projected inverse dynamics, decomposes the control law into constrained and unconstrained subspaces. Unconstrained components accomplish the motion task with a desired 6-DOF Cartesian impedance behaviour against external disturbances. Meanwhil...

The paper deals with the shape and/or topology optimization for an elastic body in unilateral contact with a rigid foundation. The contact phenomenon with Tresca friction between the surfaces of the elastic or rigid bodies is described by the elliptic variational inequality. This optimization problem consists in finding such topology of the domain occupied by the body and/or the shape of its bo...