Natural Reference Frames within Video Analysis

This study explores an alternative approach to video-based motion analysis using natural reference frames rather than relying on manual alignment. We demonstrate how the motion data itself can reveal optimal reference frames, connecting fundamental physical principles with data analysis. We present three classical mechanics experiments: uniform motion along a track, where the motion direction naturally defines the axis; circular motion of a bicycle wheel, where the center of rotation emerges as the reference origin; and projectile motion from a juggling tutorial, where gravity determines the vertical direction. This approach demonstrates how physical constraints and symmetries can naturally emerge from experimental data, providing a viable approach for introductory physics laboratories.