Accession Number:

ADP013845

Title:

The Cause of Spatial Disorientation

Descriptive Note:

Corporate Author:

HUMAN FACTORS RESEARCH INST TNO SOESTERBERG (NETHERLANDS)

Report Date:

2003-02-01

Pagination or Media Count:

13.0

Abstract:

We here present a model including visual-vestibular interactions describing the basic properties of the human spatial orientation system. It hence also explains and describes spatial disorientation. The model indicates that spatial orientation should at least be charactered by four variables linear acceleration and velocity, angular velocity, and attitude. Perception of the latter is part of the subjective vertical. Due to visual-vestibular interactions at different levels, these variables are partly independent, and may therefore behave differently. This is demonstrated by two examples concerning a takeoff. A moderate takeoff is simulated by means of a Stewart platform, a high G-load takeoff, like the catapult launch on an aircraft carrier, by a centrifuge. Model predictions are shown and concisely discussed, with further reference to previous papers on this matter. This elaboration, and the notice that we normally in case of self propelled motion need a sense of self motion for self control of body motion, leads us to the following conclusion the main cause of spatial disorientation is the indistinguishability of accelerations due to motion i.e. inertial accelerations and those due to gravity. This problem is further enhanced by a limited range of near perfection of our visual and vestibular sensors. Unfortunately, the high performance military flight environment is definitely out of that range.

Subject Categories:

  • Psychology
  • Stress Physiology

Distribution Statement:

APPROVED FOR PUBLIC RELEASE