Target Finding with a Spatially Aware Handheld Chart Display

Objective: The objective was to evaluate the use of a spatially aware handheld chart display in a comparison with a track-up fixed display configuration and to investigate how cognitive strategies vary when performing the task of matching chart symbols with environmental features under different display geometries and task constraints. Background: Small-screen devices containing both accelerometers and magnetometers support the development of spatially aware handheld maps. These can be designed so that symbols representing targets in the external world appear in a perspective view determined by the orientation of the device. Method: A panoramic display was used to simulate a marine environment. The task involved matching targets in the scene to symbols on simulated chart displays. In Experiment 1, a spatially aware handheld chart display was compared to a fixed track-up chart display. In Experiment 2, a gaze monitoring system was added and the distance between the chart display and the scene viewpoint was varied. Results: All respondents were faster with the handheld device. Novices were much more accurate with the handheld device. People allocated their gaze very differently if they had to move between a map display and a view of the environment. Conclusion: There may be important benefits to spatially aware handheld displays in reducing errors relating to common navigation tasks. Application: Both the difficulty of spatial transformations and the allocation of attention should be considered in the design of chart displays