Relational Description to Parametric Evolution of Mudras

The objective of this work is to use the relational configuration schema to describe hand postures and to simulate the posture-evolution. First, a general scheme of vocabulary for describing relational configurations is developed. Translating the conventional way of describing relationships using this scheme it is found that it is possible to evolve a structured way of picking description elements from the vocabulary which is amenable to computer implementation. This is demonstrated through a contact based description of hand posture and determination of the respective hand configuration through an optimization based inverse kinematics formulation. In the second part, grasp-evolution is simulated. A linear interpolation and Bezier interpolation between two specified Mudras or hand postures have been studied. Intermediate Mudras necessary for specification of the control polygon of the Bezier is obtained from traversal of the Mudra hierarchy studied earlier. It is found that, when a comparison is made with human performance of postural transitions, similarity of the computed transitions depend upon the number of intermediate Mudras; when this number is not large, Bezier interpolation scheme provides reasonably natural transition.