Personal computers and handheld devices provide keyboard shortcuts and swipe gestures to enable users to efficiently switch between applications, whereas today’s virtual reality (VR) systems do not. In this work, we present an exploratory study on user interface aspects to support efficient switching between worlds in VR. We created eight interfaces that afford previewing and selecting from the available virtual worlds, including methods using portals and worlds-in-miniature (WiMs). To evaluate these methods, we conducted a controlled within-subjects empirical experiment (N=22) where participants frequently transitioned between six different environments to complete an object collection task. Our quantitative and qualitative results show that WiMs supported rapid acquisition of high-level spatial information while searching and were deemed most efficient by participants while portals provided fast pre-orientation. Finally, we present insights into the applicability, usability, and effectiveness of the VR world switching methods we explored, and provide recommendations for their application and future context/world switching techniques and interfaces.

In most cases, retaining memories of things we have experienced in the past is desirable, but in some cases, we want to clear our minds so that we may focus completely on subsequent activities. When someone switches from one task to another, they commonly incur some “cognitive residue” where some of their cognitive resources such as working memory and attention remain devoted to their previous task even after they try to switch their focus to their new task. This residue could have a negative impact on their performance in the next task, and in such circumstances, it is important to reduce that residue. In this paper, we explore the concept of cognitive residue in the context of switching between virtual reality (VR) environments. We conducted a human-subject experiment (N=24) with a spatial recall task to investigate how different visual transitions might reduce participants’ spatial cognitive residue. In this instance, more errors on the recall task corresponds to less spatial cognitive residue. We found that transitions that lasted one minute successfully reduced spatial cognitive residue: they significantly reduced participants’ abilities to recall the positions of objects in their previous VE compared to an instantaneous cut transition. Additionally, for transitions that showed a nature scene, greater head movement significantly correlated with more spatial memory errors (i.e., less spatial cognitive residue). We discuss how these findings can be applied to support users transitioning between virtual tasks and environments in VR task switching scenarios.

Although areas devastated by natural disasters must be promptly reconstructed, reconstruction works involving construction machinery are dangerous and bring a significant risk of a second disaster. A remote construction system is thus often used, which enables an operator to conduct reconstruction work from a remote and safe place while viewing on-site videos. However, the remote construction has a major problem: it has much lower work efficiency than manned construction because videos are delayed and impaired in a wireless network environment. In this paper, we present a remote construction system using our proposed adaptive video streaming method that dynamically adjusts the video bitrate on the basis of the predicted communication throughput variation. The experiments show that the proposed remote construction system using adaptive video streaming reduces operation time by 25.5%, which corresponds to a 34.3% improvement in work efficiency.

In the construction industry, remote construction has been introduced in specified cases such as restoration work after natural disasters in order to improve safety. Remote construction can also contribute to allocating limited labor resources efficiently and solving the labor scarcity problem. For this, long-distance remote construction though networks such as a wireless local area network (WLAN) and the Internet must be made possible. However, long-distance networks can have large transmission delays and packet loss, which cause bottlenecks that result in low operability and increased workload. We propose a remote construction system based on adaptive remote control techniques for improving video streaming and operation with considerations made for delays and packet loss. We also conduct an experiment to evaluate how the proposed remote construction system reduces workloads. Our experiment shows that the proposed system reduces the number of manipulations for a certain task by 25%. It also reduces the duration of operations by 16%, which corresponds to a 20% improvement in work efficiency.