A three-dimensional motion tracking method in graphonomic research: Using rigid bodies and object-oriented programming

Abstract

This paper describes the technical part of a methodology involving three-dimensional motion tracking as applied to graphonomic research. A simple technique is described by means of which the rotations of joints in the arm, hand, and finger can be recorded in addition to three-dimensional pen-tip displacements. For this purpose, the Optotrak system is used and a method which makes use of rigid bodies defining the position and orientation of the segments of a writer's arm. Furthermore, it is shown that by making use of a visually-oriented, component-based programming environment such as Delphi, the development of software needed to conduct experiments can be simplified considerably.