In our digital art, we design a folding fan as an interactive magic device. You can use it to play with gas around the world of illusions. Although gas could not be seen in our real world, we still want to interact with it in our illusions by the element of bubble shadows. Opening and swinging the folding fan can blow the bubble shadows away; closing and swinging it can break bubbles. If the ma...

In running, the spring-like axial behavior of stance limbs is a well-known and remarkably general feature. Here we consider how the rotational behavior of limbs affects running stability. It is commonly observed that running animals retract their limbs just prior to ground contact, moving each foot rearward towards the ground. In this study, we employ a conservative spring-mass model to test th...

The purpose of this study was to examine trunk rotational patterns and weight transfer patterns that may differentiate swing skill level in golfers. Thirteen skilled golfers (mean handicap = 0.8 ± 2.6) and seventeen low skilled golfers (mean handicap = 30.8 ± 5.5) participated in this study. Kinematic and kinetic data were obtained through high-speed 3-D videography and force plates while the p...

When we walk, there are infinite number of possible trajectories for leg swing. How does the brain design the trajectory? As a candidate for the strategy of the trajectory selection, we assessed the criterion of the minimization of the energy cost in this study. We computed the optimal leg trajectory that minimizes the energy cost during the swing phase under the boundary condition that enables...