This paper discusses the dynamics computation of closed kinematic chains, especially those found in motions of human gures. A number of e cient dynamics computation algorithms have been established in robotics for open kinematic chains and particular types of closed kinematic chains, such as parallel ve-bar link mechanisms and the Stewart platform. The dynamics computation of closed kinematic c...

This paper presents a coordinate-invariant differential geometric analysis of manipulability for closed kinematic chains containing active and passive joints. The formulation treats both redundant and nonredundant mechanisms, as well as over-actuated and exactly actuated ones, in a uniform manner. Dynamic characteristics of the mechanism and manipulated object can also be naturally included by ...

we design a two-stage scheme to consider trajectory planning problem of two mobile manipulators for cooperative transportation of a rigid body in presence of static obstacles. within the first stage, regarding the static obstacles we develop a method that searches the workspace for the shortest possible path between start and goal configurations by constructing a graph on a portion of the confi...

The problem of force distribution in systems involving multiple frictional contacts between actively coordinated mechanisms and passive objects is examined. The special case in which the contact interaction can he modeled by three components of forces (zero moments) is particularly interesting. The Moore-Penrose Generalized Inverse solution for such a model (point contact) is shown to yield a s...

This paper presents a coordinate-invariant differential geometric analysis of kinematic singularities for closed kinematic chains containing both active and passive joints. Using the geometric framework developed in Park and Kim (1996) for closed chain manipulability analysis, we classify closed chain singularities into three basic types: (i) those corresponding to singular points of the joint ...

This paper deals with the motion interpolation of an object that satisfies the kinematic constraints imposed by planar 6R closed chains. The paper brings together the well-known kinematics of planar 6R closed chains and the freeform rational motions to synthesize the constrained piecewise rational motions in the Cartesian space. The methodology adopted in this paper is based on transforming the...

Kinematic loop-closure constraints significantly increase the difficulty of motion planning for articulated mechanisms. Configurations of closed-chain mechanisms do not form a single manifold, easy to parameterize, as the configurations of open kinematic chains. In general, they are grouped into several subsets with complex and a priori unknown topology. Sampling-based motion planning algorithm...

In this paper, kinematic modeling and singularity analysis of a three DOF redundant parallel manipulator has been elaborated in detail. It is known, that on the contrary to series manipulators, the forward kinematic map of parallel manipulators involves highly coupled nonlinear equations, whose closed-form solution derivation is a real challenge. This issue is of great importance noting that th...