Influence of Gravity on Exocentric and Egocentric Target Cueing Using Augmented Reality
During payload operations astronauts are guided by sequential directives displayed on a laptop computer using an exocentric presentation scheme for task guiding. Such an approach forces the astronaut to constant changes of focus that can cause loss of concentration and attention, as well as can be the primary reason for sequence errors resulting in a faulty task termination. To ease astronauts' work and ensure successful task performance new interface technologies are required. By bridging the gap between the physical reality and digital information, Augmented Reality (AR) keeps the focus on the task to fulfill and offers user- centered operations by an egocentric display. Beside the display, AR interface can differ in providing the visual information for localizing users’ attention. While egocentric visualizations maintain the principal characteristic required for AR interfaces by 3D registered information, exocentric visualizations are presented as head-up display information and approved methods to navigate the user towards off-screen objects. Using a visuomotor task (visual search, operation task) we will investigate the influence of altered gravity on human performance and workload by comparing exocentric with egocentric displays and presentation schemes in a within-subject user study. To differentiate visuomotor deficits we will use common performance metrics. Workload effects will assess with subjective, physiological and secondary task performance. For evaluating the physiological workload we intend to assess and analyze cardiovascular parameters such as the heart rate variability, the heart frequency and the blood pressure. We expect that under altered gravity, especially under short-term microgravity, the egocentric presentation of task directives using the Augmented Reality condition outperforms exocentric conditions by increased performance and decreased workload. We will also perform head movement analysis resulted from the visual search process and expect significant findings for the AR condition that offers visual search by egocentric navigation providing head movements in given horizontal, vertical and oblique directions.