This paper discusses the design and current capabilities of a new software tool, dVC, capable of simulating planar systems of bodies experiencing unilateral contacts with friction. Since different problems require different levels of accuracy, dVC provides user-selectable body types (rigid or locally-compliant), motion models (first-order, quasi-static, dynamic), and several state-of-the-art time-stepping methods. One can also choose to include friction between each body and the plane of motion. To support optimal and robust part design, dVC also allows on-the-fly changes to parameters of the geometric and physical models. The results obtained for three representative planar problems are presented: the design of a passive part-orienting device, the planning of a mesoscale assembly operation, and the design of a grasp strategy.

In this paper, we use a linear complementarity problem (LCP) formulation of rigid body dynamics with unilateral contacts to obtain definitions for contact modes. We show how the complementary cones of the LCP correspond to each of the intuitive contact modes: slide right, slide left, roll and separate. These complementary cones allow us to make rigorous definitions for contact modes in three-dimensional systems, where our intuitive understanding fails.