We study the dual mixed finite element approximation of unilateral contact problems. Based on the dual mixed variational formulation with three unknowns (stress, displacement and the displacement on the contact boundary), the a priori error estimates have been established for both conforming and nonconforming finite element approximations. A Uzawa type iterative algorithm is developed to solve ...

In prior work we proposed a class of physically-based models suitable for animating /lezible objects in simulated physical environments {ll. Our original formulation works well in practice for models whose shapes are moderately to highly deformable, but it tends to become numerically ill-conditioned as we increase the rigidity of the models. The present paper develops an alternative formulation...

We propose a formulation capable of measuring the complexity of kinematic chains at the conceptual stage in robot design. First, the complexity of the three basic lower kinematic pairs, the revolute, the prismatic and the cylindrical pairs, is proposed. Then, a formulation of the complexity of kinematic chains is introduced. Next, the complexity of the basic displacement subgroups generated by ...

This paper presents a nonlinear formulation to model flexible-link robots based on finite element approach. To derive nonlinear dynamic equations of the flexible-link robot, links are modeled by some finite elements, and Lagrange’s principle is used for dynamic modeling. A local coordinate system is attached to each link and the local displacement of an arbitrary point is formulated based on no...

Ahatract-We introduce a displacement-pressure (u/p) finite element formulation for the geometrically and materially nonlinear analysis of compressible and almost incompressible solids. The u/p formulation features the a priori replacement of the pressure computed from the displacement field by a separately interpolated pressure; this replacement is petformed without reference to any specific ma...

In this paper we analyze a new dual mixed formulation of the elastodynamic system in polygonal domains. In this formulation the symmetry of the strain tensor is relaxed by the rotational of the displacement. For the time discretization of this new dual mixed formulation, we use an explicit scheme. After the analysis of stability of the fully discrete scheme, L∞ in time, L2 in space a priori err...

An ordinary state-based peridynamic formulation is developed to analyse cubic polycrystalline materials for the first time in the literature. This new approach has the advantage that no constraint condition is imposed on material constants as opposed to bond-based peridynamic theory. The formulation is validated by first considering static analyses and comparing the displacement fields obtained...

In this paper, a self-consistent boundary element method is introduced to predict overall properties of a cracked bimaterial plate. The boundary element (BE) formulation is developed based on Green’s function for displacement discontinuity of a bimaterial solid and potential variational principles. The self-consistent method is then introduced into the BE formulation to provide an effective mea...