Modeling Human Perceptual Thresholds in Self-Motion Perception

Abstract

Knowledge of thresholds for perception of inertial motion is needed for the design of simulator motion filters. Experiments have generally been done to measure these thresholds in isolation, one motion at the time. In vehicle simulation however, several motions occur concurrently. In a flight simulator, both inertial and visual cues are provided and motion is rarely in a single axis. Previous experiments have shown that inertial thresholds are modified when simultaneous inertial cues or visual and inertial cues are provided. In this paper, pitch motion thresholds are measured for 5 frequencies between 0.6 and 10 rad/s. Thresholds are measured in two situations: in the dark, single axis motion (sensory thresholds) and in the dark, with a heave masking cue (indifference thresholds). The heave motion has an amplitude of 0.02 g and is of the same frequency as the pitch motion. The effect of the masking cue on the pitch rate perception threshold frequency description is not significant. The measured thresholds, both with and without masking cue, fit known models for the Semi-Circular Canals transfer function.