More does not Mean Better: Effects of Spatial Snapshot Annotations on Remote Collaboration

Abstract

Remote collaboration can greatly benefit from the improved reconstruction and tracking capabilities of optical see-through head-mounted displays. A remote helper can efficiently assist a local worker and convey complex instructions by placing 3D instructions into the environment. If a high quality reconstruction is not available, spatial snapshot annotations that utilize only 6DOF device tracking data present an opportunity to facilitate efficient communications. While different techniques have been explored for annotation creation from multiple spatial snapshots on handheld devices, they have not been evaluated in a remote collaboration scenario or on optical see-through head-mounted displays (OST-HMDs). In this paper, we present an empirical comparison of three annotation creation methods for spatial snapshots in a remote assembly support scenario for OST-HMDs. ViewAR presents only an annotated snapshot created by the remote helper; DepthAR places 3D annotations at the estimated surface of the environment, while SlidAR allows adjustments of the location at which the annotation is placed. Our study with 24 participants showed that all methods were well received. We found that participants used different approaches to complete the task to mitigate the shortcomings of the techniques. Our findings provide insights for the future design of remote collaboration systems based on spatial snapshots.