Movement Time for Pointing Tasks in Real and Augmented Reality Environments

Human-virtual target interactions are becoming more and more common due to the emergence and application of augmented reality (AR) devices. They are different from interacting with real objects. Quantification of movement time (MT) for human-virtual target interactions is essential for AR-based interface/environment design. This study aims to investigate the motion time when people interact with virtual targets and to compare the differences in motion time between real and AR environments. An experiment was conducted to measure the MT of pointing tasks on the basis of both a physical and a virtual calculator panel. A total of 30 healthy adults, 15 male and 15 female, joined. Each participant performed pointing tasks on both physical and virtual panels with an inclined angle of the panel, hand movement direction, target key, and handedness conditions. The participants wore an AR head piece (Microsoft Hololens 2) when they pointed on the virtual panel. When pointing on the physical panel, the participants pointed on a panel drawn on board. The results showed that the type of panel, inclined angle, gender, and handedness had significant (p < 0.0001) effects on the MT. A new finding of this study was that the MT of the pointing task on the virtual panel was significantly (p < 0.0001) higher than that of the physical one. Users using a Hololens 2 AR device had inferior performance in pointing tasks than on a physical panel. A revised Fitts's model was proposed to incorporate both the physical-virtual component and inclined angle of the panel in estimating the MT. This model is novel. The index of difficulty and throughput of the pointing tasks between using the physical and virtual panels were compared and discussed. The information in this paper is beneficial to AR designers in promoting the usability of their designs so as to improve the user experience of their products.

Automated summary

With the emergence and application of augmented reality (AR) devices, human-virtual target interactions are becoming more common. This study aims to investigate the motion time (MT) when people interact with virtual targets and compare the differences in motion time between real and AR environments. An experiment was conducted with 30 healthy adults performing pointing tasks on physical and virtual calculator panels. The results showed that the type of panel, inclined angle, gender, and handedness had significant effects on the MT, with the MT on the virtual panel being higher than the physical one. A revised Fitts's model was proposed to estimate the MT in both physical-virtual and inclined panel situations. The information in this study is beneficial for AR designers to improve the usability and user experience of their designs.