A three dimensional visor display system for the postural stability analysis

A measurement system was developed to quantify the effect of altering visual feedback information on human body sway. A three-dimensional visor display was proposed to provide the eyes with stereoscopic vision depending on head motion. A pair of CCD cameras and a pair of liquid-crystal displays were used to show wide images with binocular parallax to the test subject. The head motion on the frontal plane was measured online by using the image processing unit for the video signal obtained from the CCD cameras, and an ultrasonic distance sensor was used to measure the rotation of the head on the horizontal plane. In the experiments, the subject used head rotation to track a visual reference signal. The results from the experiments reveal that the vestibular information contradictory to the visual information increased body sway