ARTHROKINEMATICS COMPUTATIONS FOR DESIGN OF BONE-ANCHORED TRANSRADIAL AMPUTATION PROSTHESES THROUGH ELASTOKINEMATIC MODELING OF HUMAN FOREARM

Abstract

Pronation and supination of forearm is an essential movement required to perform activities of daily living and loss of this mobility leads to significant loss of upper limb function. An accurate kinematic model that can precisely simulate bone articulations during forearm rotation is mandatory for optimal design of prosthetic and rehabilitation devices. It is also helpful for better planning of treatments and rehabilitation protocols. Distinctive features that define patterns of linkages movements during forearm rotation are identified and segregated in the form of attributes. The trend and magnitude inferences of these attributes are based on earlier works. Structures of mechanically analogous mechanisms are analyzed and closed form solutions of attributes are established for existing models. Evaluation of simulated kinematics of these mechanisms on the basis of attributes reveal that, still there are some attributes that have previously been remained unnoticed and are also required to be incorporated. Rectification of identified discrepancies is proposed through introduction of a new three degree of freedom surrogate mechanism which is fitted with virtual springs to imitate the elastic effects of joints.