Athletes and artisans gets a tacit knowledge in longtime experiences. The tacit knowledge is impossible to tell other persons directly. However, if common features should reside in their experiences, we will assume those are one of common elements of tacit knowledge in experts and requirements to be experts. In this paper, we measured a bat swing motion by using 3D motion capture systems, and analyzed a muscle power of a lower limb. In the analysis, we estimated a muscle power of a lower limb of regular players and beginner players in high school baseball by using kinetic analysis systems, and extracted common features of expert players with comparing these data.
