In human swimming, there are many situations in which the target of the analysis is not only the swimmer but also other swimmers or other equipment, such as synchronized swimming by multiple swimmers, swimming with fins, and so on. The objective of this study was to extend the swimming human simulation model SWUM so that it could handle the dynamic behavior of multiple rigid bodies and could freely describe the mechanical interactions among the rigid bodies. In this paper, the outline of SWUM is described first. The extension to the multi agent/object simulation and its implementation are explained next. Finally, its validity and usefulness are examined by discussing three examples of analysis. The first example was synchronized swimming by three swimmers. From the simulation results, it was found that the three swimmers gradually gathered, and finally the swimmers' upper limbs stably formed a hexagon. The second example was monofin swimming. The monofin was divided into five rigid plates in this simulation in order to represent its elastic deformation. From the simulation results, it was found that the swimmer accelerated at the moments of downward and upward kicks. The third example was the shooting motion in water polo. From the simulation results, it was found that the ball was smoothly released and flew in an appropriate direction. Since reasonable results were obtained in these examples of analysis, the validity and usefulness of the extension were confirmed.
2010 by The Japan Society of Mechanical Engineers