Event Identification Via Dynamically Governed Trajectory Forms
Michael M. Muchisky · 2019
This chapter shows that trajectory forms are a source of visual information by demonstrating that observers are sensitive to subtle changes in trajectory forms. It also shows that these sensitivities are not just a function of kinematic differences, but are determined by dynamical properties that produce various trajectory forms. A ball, depicted in computer-generated displays as a dark circle on a light textureless background, moved through two complete cycles as a bob on a pendulum. A standard display was created using only gravity. Without friction, the amplitude of the swings remained constant. Displays of Damped (DP) and Injected (IP) Pendulums were created by simulating air resistance and manipulating the sign on the damping. A gravitationally determined orientation of the pendulum acted as a fixed point in the dynamics, either as an attractor for the DP or a repeller for the IP.