Analysis System for Falling Motion of Snowflakes Using Sequential Images

Abstract

Falling snowflakes were photographed simultaneously by two CCD cameras having different shutter speeds. The high speed camera was used for determining the shape and the low speed one to measure the motion. The shape of a snowflake and its falling motion are analyzed using continuously photographed image frames. The falling motion of a snowflake is calculated by tracing its position in subsequent frames. Relationships between shape and motion parameters were analyzed. Data indicate that tilt angle and falling direction were perpendicular to each other. It is considered that snowflakes encounter more resistance from air toward the upper direction during their fall.