Understanding the two-step nonvisual omnidirectional guidance for target acquisition in 3D spaces

Providing directional guidance is important especially for exploring unfamiliar environments. However, most studies are limited to two-dimensional guidance when many interactions happen in 3D spaces. Moreover, visual feedback that is often used to communicate the 3D position of a particular object may not be available in situations when the target is occluded by other objects or located outside of one’s field of view, or due to visual overload or light conditions. Inspired by a prior finding that showed users’ tendency of scanning a 3D space in one direction at a time, we propose two-step nonvisual omnidirectional guidance feedback designs varying the searching order where the guidance for the vertical location of the target (the altitude) is offered to the users first, followed by the horizontal direction of the target (the azimuth angle) and visa versa. To investigate its effect, we conducted the user study with 12 blind-folded sighted participants. Findings suggest that our proposed two-step guidance outperforms the default condition with no order in terms of task completion time and travel distance, particularly when the guidance in the horizontal direction is presented first. We plan to extend this work to assist with finding a target in 3D spaces in a real-world environment.