Head roll compensation in a visually coupled HMD: Considerations for helicopter operations

The helmet-mounted display (HMD) research program at the Flight Research La boratory of the National Research Council of Canada examined the effects of HMD camera platform dynamics on pilot workload. Many currently fielded vis ually coupled HMD systems do not reproduce head movements in the roil axis which can lead to the presentation of visual information that is not consis tent with vestibular and proprioceptive information. Hypothesis: Our hypoth esis was that this sensory conflict can induce motion sickness and increase pilot workload. Methods: To examine this premise, three pilots new a serie s of standardized maneuvers with or without roll compensation in the camera platform of a visually coupled HMD system. Results: Increases in motion si ckness symptoms and pilot workload were noted during complex, high-workload maneuvers when no roil compensation was present in the camera platform. Du ring the most demanding maneuvers, the lack of roll compensation in the cam era platform made it difficult for the evaluation pilot to control the heli copter. Conclusions: Roll compensation in visually coupled HMD systems redu ces pilot workload and motion sickness during critical flight periods where pilot workload may already be considerable.