We present two geometric descriptions of the frictional properties of a rigid body sliding on a planar surface. The limit surface LS, from classical plasticity theory, is the boundary of the set of all possible frictional forces and moments that can be sustained by the frictional interface. Zhukovskii’s moment finction is the frictional moment as a function of the instantaneous center of rotati...

We consider the problem of planning manipulation tasks in which rigid body dynamics are significant and the rigid bodies undergo frictional contacts. We develop a dynamic model with frictional compliant contacts, and a time-stepping algorithm that lends itself to finding trajectories with constraints on the starting and goal conditions. Because we explicitly model the local compliance at the co...

Abstract-Following the idea of Bowie and Freese we consider a crack in a field of pure bending. The crack is closed over part of its extent, and the two crack faces in contact are allowed to slip under frictional constraints. The solution is constructed under the assumption that the applied loading is monotonically increased. It is discovered, however, that it is possible to analyze unloading b...

For robotic systems to automatically plan and execute manipulation tasks involving intermittent contact, one must be able to accurately predict the motions of the manipulated objects. Not surprisingly, many of the important manipulation problems that could yield to closed-form analysis have been solved and studied thoroughly. Problems characterized by intermittent contact are one particularly i...

Abstract Frictional losses occur in tapered roller bearings, particularly at low rolling speeds, which pose a risk of wear. The increased friction are result insufficient lubricant film thicknesses the and rib contact. Micro-lubrication dimples can be used to induce additional into contact zone minimize friction. aim this paper is therefore implement suitable machining strategy for production d...

We show that in slowly generated two-dimensional packings of frictional spheres, a significant fraction of the friction forces lie at the Coulomb threshold-for small pressure p and friction coefficient mu , about half of the contacts. Interpreting these contacts as constrained leads to a generalized concept of isostaticity, which relates the maximal fraction of fully mobilized contacts and cont...