A Dynamical Analysis of Kneading Using a Motion Capture Device

Abstract

Physical skills such as playing the musical instrument are hard to learn and take long time to master. To investigate what makes physical skills so dificult to learn and how we can evaluate the level of skills, we examined the kneading in ceramic art, an action to prepare the clay for shaping and studied the physical movements of both the learners and experts. Kneading is an appropriate sample of physical skill for studying the body movement because all the parts of body need to be coordinated to accomplish the task. The task is not hopelessly difficult for the complete novices to follow the instruction although the end result is not satisfactory. It normally takes about three years to master the kneading skill. It is also relatively easy to judge how well the subjects accomplished the task by observing the shape of the clay. After careful examination of the movement using video tapes, we employed a motion capture device to collect the data of movement from an expert, an experienced person, and three novices. We discovered that the expert elegantly splits his body into two parts, torso and arms, and effectively coordinates these two parts while kneading the clay.