Abstract
In this paper, a three-dimensional parallel solution scheme for inverse dynamics of link mechanisms is described, which is already proposed in a two-dimensional case and applied in several in-plane motions. In this theory, the entire system is subdivided into finite elements and evaluated as a continuum. A single-link structure of a pin joint and a rigid bar is expressed by using the shifted integration (SI) technique, which is usually used in finite element analyses of framed structures. This scheme calculates nodal forces by evaluating equations of motion in a matrix form, and thus information from the entire system can be handled in parallel. The obtained nodal forces are then converted to the joint torque in the system. Simple numerical tests on two-dimensional and three-dimensional open-loop link mechanisms are carried out to compare them with other schemes, and some tests on closed-loop and continuously transforming mechanisms are carried out to confirm the flexibility of the scheme.