THE DISTAL-TO-PROXIMAL INCREASE OF LINK LENGTH ALONG THE HUMAN KINEMATIC CHAIN - AN EXPONENTIAL PROGRESSION OF WORK-SPACE EXTENSION

The goal of this note is to report a gross anthropometric relationship that relates quantitatively the length of links to their rank in the distal-to-proximal succession of skeletal links in humans. This relati onship, an exponential function, is conceptually simple, applies to a satisfactory approximation to the whole kinematic chain from the level of the finger to that of the whole extended body, and suffers low bet ween-subject variability. Remarkably easy to assess empirically throug h simple measurements, the relationship in question may be of interest for theoretical biologists and roboticists.