Visual based human motion analysis: Mapping gestures using a puppet model

This paper presents a novel approach to analyze the appearance of human motions with a simple model i.e. mapping the motions using a virtual marionette model. The approach is based on a robot using a monocular camera to recognize the person interacting with the robot and start tracking its head and hands. We reconstruct 3-D trajectories from 2-D image space (IS) by calibrating and fusing the camera images with data from an inertial sensor, applying general anthropometric data and restricting the motions to lie on a plane. Through a virtual marionette model we map 3-D trajectories to a feature vector in the marionette control space (MCS). This implies inversely that now a certain set of 3-D motions can be performed by the (virtual) marionette system. A subset of these motions are considered to convey information (i.e. gestures). Thus, we are aiming to build up a database which keeps the vocabulary of gestures represented as signals in the MCS. The main contribution of this work is the computational model of the IS-MCS-Mapping. We introduce the guide robot '' Nicole '' to place our system in an embodied context. We sketch two novel approaches to represent human motion (i.e. Marionette Space and Labananalysis). We define a gesture vocabulary organized in three sets (i.e. Cohens Gesture Lexicon, Pointing Gestures and Other Gestures).